1,437 results on '"gliding motility"'
Search Results
402. A Putative O-Linked β-N-Acetylglucosamine Transferase Is Essential for Hormogonium Development and Motility in the Filamentous Cyanobacterium Nostoc punctiforme
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Ye Won Cho, Samantha D. Splitt, Rachelle Kim, Osagie H. Omoruyi, Behzad Khayatan, Jessica Huynh, Adriana P. Pantoja, Julia K. Peng, Jun Sang Park, Monica H. Cheng, Douglas D. Risser, Divleen K. Bains, and Mason Y. Tian
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0301 basic medicine ,Gliding motility ,Movement ,030106 microbiology ,Mutant ,Motility ,Biology ,N-Acetylglucosaminyltransferases ,Microbiology ,03 medical and health sciences ,Bacterial Proteins ,Hormogonium ,Nostoc ,Symbiosis ,Molecular Biology ,Heterocyst ,Nostoc punctiforme ,Gene Expression Profiling ,Wild type ,Gene Expression Regulation, Bacterial ,biology.organism_classification ,Biochemistry ,Fimbriae, Bacterial ,Mutation ,Genetic screen ,Research Article - Abstract
Most species of filamentous cyanobacteria are capable of gliding motility, likely via a conserved type IV pilus-like system that may also secrete a motility-associated polysaccharide. In a subset of these organisms, motility is achieved only after the transient differentiation of hormogonia, which are specialized filaments that enter a nongrowth state dedicated to motility. Despite the fundamental importance of hormogonia to the life cycles of many filamentous cyanobacteria, the molecular regulation of hormogonium development is largely undefined. To systematically identify genes essential for hormogonium development and motility in the model heterocyst-forming filamentous cyanobacterium Nostoc punctiforme , a forward genetic screen was employed. The first gene identified using this screen, designated ogtA , encodes a putative O-linked β- N -acetylglucosamine transferase (OGT). The deletion of ogtA abolished motility, while ectopic expression of ogtA induced hormogonium development even under hormogonium-repressing conditions. Transcription of ogtA is rapidly upregulated (1 h) following hormogonium induction, and an OgtA-GFPuv fusion protein localized to the cytoplasm. In developing hormogonia, accumulation of PilA but not HmpD is dependent on ogtA . Reverse transcription-quantitative PCR (RT-qPCR) analysis indicated equivalent levels of pilA transcript in the wild-type and Δ ogtA mutant strains, while a reporter construct consisting of the intergenic region in the 5′ direction of pilA fused to gfp produced lower levels of fluorescence in the Δ ogtA mutant strain than in the wild type. The production of hormogonium polysaccharide in the Δ ogtA mutant strain is reduced compared to that in the wild type but comparable to that in a pilA deletion strain. Collectively, these results imply that O -GlcNAc protein modification regulates the accumulation of PilA via a posttranscriptional mechanism in developing hormogonia. IMPORTANCE Filamentous cyanobacteria are among the most developmentally complex prokaryotes. Species such as Nostoc punctiforme develop an array of cell types, including nitrogen-fixing heterocysts, spore-like akinetes, and motile hormogonia, that function in dispersal as well as the establishment of nitrogen-fixing symbioses with plants and fungi. These symbioses are major contributors to global nitrogen fixation. Despite the fundamental importance of hormogonia to the life cycle of filamentous cyanobacteria and the establishment of symbioses, the molecular regulation of hormogonium development is largely undefined. We employed a genetic screen to identify genes essential for hormogonium development and motility in Nostoc punctiforme . The first gene identified using this screen encodes a eukaryotic-like O-linked β- N -acetylglucosamine transferase that is required for accumulation of PilA in hormogonia.
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- 2017
403. A forward genetic screen identifies a negative regulator of rapid Ca2+-dependent cell egress (MS1) in the intracellular parasite Toxoplasma gondii
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Jan Schröder, Leonard J. Foster, Nichollas E. Scott, Anthony T. Papenfuss, Alessandro D. Uboldi, Adele M. Lehane, Christopher J. Tonkin, James M. McCoy, Dongdi Li, and Rebecca Stewart
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0301 basic medicine ,030102 biochemistry & molecular biology ,Gliding motility ,Kinase ,Intracellular parasite ,Mutant ,Calcium-Binding Proteins ,Protozoan Proteins ,Cell Biology ,Biology ,Biochemistry ,Microbiology ,Cell biology ,03 medical and health sciences ,030104 developmental biology ,Lytic cycle ,stomatognathic system ,Phosphorylation ,Calcium Signaling ,Signal transduction ,Molecular Biology ,Protein Kinases ,Toxoplasma ,Genetic screen - Abstract
Toxoplasma gondii, like all apicomplexan parasites, uses Ca2+ signaling pathways to activate gliding motility to power tissue dissemination and host cell invasion and egress. A group of "plant-like" Ca2+-dependent protein kinases (CDPKs) transduces cytosolic Ca2+ flux into enzymatic activity, but how they function is poorly understood. To investigate how Ca2+ signaling activates egress through CDPKs, we performed a forward genetic screen to isolate gain-of-function mutants from an egress-deficient cdpk3 knockout strain. We recovered mutants that regained the ability to egress from host cells that harbored mutations in the gene Suppressor of Ca2+-dependent Egress 1 (SCE1). Global phosphoproteomic analysis showed that SCE1 deletion restored many Δcdpk3-dependent phosphorylation events to near wild-type levels. We also show that CDPK3-dependent SCE1 phosphorylation is required to relieve its suppressive activity to potentiate egress. In summary, our work has uncovered a novel component and suppressor of Ca2+-dependent cell egress during Toxoplasma lytic growth.
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- 2017
404. Characterization of the Porphyromonas gingivalis Type IX Secretion Trans-envelope PorKLMNP Core Complex
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Julien Stathopulos, Abdelrahim Zoued, Christine Kellenberger, Maxence S. Vincent, Alain Roussel, Philippe Leone, Mickaël J. Canestrari, Christian Cambillau, Eric Cascales, Bérengère Ize, Laboratoire d'ingénierie des systèmes macromoléculaires (LISM), Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Aix Marseille Université (AMU), Architecture et fonction des macromolécules biologiques (AFMB), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), and Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)
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0301 basic medicine ,Gliding motility ,[SDV]Life Sciences [q-bio] ,030106 microbiology ,channel ,membrane proteins ,Biochemistry ,Flavobacterium ,03 medical and health sciences ,membrane complex ,protein secretion ,Tannerella forsythia ,Secretion ,Type IX secretion ,[SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology ,Porphyromonas ,[SDV.BBM.BC]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biochemistry [q-bio.BM] ,Molecular Biology ,Porphyromonas gingivalis ,periodontitis ,biology ,[SDV.BBM.BS]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Structural Biology [q-bio.BM] ,Chemistry ,toxins ,[SDV.BBM.BM]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Molecular biology ,[SDV.BBM.MN]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Molecular Networks [q-bio.MN] ,Cell Biology ,biology.organism_classification ,[SDV.MP.BAC]Life Sciences [q-bio]/Microbiology and Parasitology/Bacteriology ,Cell biology ,[SDV.BBM.BC]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biomolecules [q-bio.BM] ,Bacterial adhesin ,[SDV.BBM.BP]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biophysics ,[SDV.BBM.BS]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biomolecules [q-bio.BM] ,stomatognathic diseases ,Secretory protein ,Membrane protein ,T9SS ,protein transport ,gingipains ,gliding motility ,Cell envelope ,gingivitis - Abstract
International audience; The transport of proteins at the cell surface of Bacteriodetes depends on a secretory apparatus known as Type IX secretion system (T9SS). This machine is responsible for the cell surface exposition of various proteins such as adhesins required for gliding motility in Flavobacteria, S-layer components in Tannerella forsythia and tooth tissue-degrading enzymes in the oral pathogen Porphyromonas gingivalis. While a number of subunits of the T9SS have been identified, we lack details on the architecture of this secretion apparatus. Here we provide evidence that five of the genes encoding the core complex of the T9SS are co-transcribed, and that the gene products are distributed in the cell envelope. Protein-protein interaction studies then revealed that these proteins oligomerize and interact through a dense network of contacts.
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- 2017
405. More than gliding: involvement of gldD and gldG in the virulence of Flavobacterium psychrophilum
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Esther Gómez, Brigitte Kerouault, Céline Henry, David Pérez-Pascual, Eric Duchaud, Tatiana Rochat, Jean François Bernardet, Fabienne Neulat-Ripoll, Edwige Quillet, José A. Guijarro, Duchaud, Eric, Unité de recherche Virologie et Immunologie Moléculaires (VIM (UR 0892)), Institut National de la Recherche Agronomique (INRA), Université Paris Saclay (COmUE), Universidad de Oviedo [Oviedo], MICrobiologie de l'ALImentation au Service de la Santé (MICALIS), Institut National de la Recherche Agronomique (INRA)-AgroParisTech, Génétique Animale et Biologie Intégrative (GABI), and European Project: 262336,EC:FP7:INFRA,FP7-INFRASTRUCTURES-2010-1,AQUAEXCEL(2011)
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0301 basic medicine ,Microbiology (medical) ,Gliding motility ,030106 microbiology ,Mutant ,lcsh:QR1-502 ,Virulence ,Flavobacterium psychrophilum ,Biology ,Microbiology ,lcsh:Microbiology ,03 medical and health sciences ,Pathogen ,Original Research ,fish-pathogenic bacteria ,Microbiology and Parasitology ,Biofilm ,gliding motility ,secretion ,T9SS ,virulence ,Oncorhynchus mykiss ,Microbiologie et Parasitologie ,[SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology ,Proteome ,Bacterial outer membrane - Abstract
International audience; A fascinating characteristic of most members of the genus Flavobacterium is their ability to move over surfaces by gliding motility. Flavobacterium psychrophilum, an important pathogen of farmed salmonids worldwide, contains in its genome the 19 gld and spr genes shown to be required for gliding or spreading in Flavobacterium johnsoniae; however, their relative role in its lifestyle remains unknown. In order to address this issue, two spreading deficient mutants were produced as part of a Tn4351 mutant library in F. psychrophilum strain THCO2-90. The transposons were inserted in gldD and gldG genes. While the wild-type strain is proficient in adhesion, biofilm formation and displays strong proteolytic activity, both mutants lost these characteristics. Extracellular proteome comparisons revealed important modifications for both mutants, with a significant reduction of the amounts of proteins likely transported through the outer membrane by the Type IX secretion system, indicating that GldD and GldG proteins are required for an effective activity of this system. In addition, a significant decrease in virulence was observed using rainbow trout bath and injection infection models. Our results reveal additional roles of gldD and gldG genes that are likely of importance for the F. psychrophilum lifestyle, including virulence.
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- 2017
406. Type IV Pili-Dependent Motility as a Tool to Determine the Activity of c-di-GMP Modulating Enzymes in Myxococcus xanthus
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Dorota Skotnicka and Lotte Søgaard-Andersen
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0301 basic medicine ,biology ,Gliding motility ,Chemistry ,Motility ,Heterologous ,Phosphodiesterase ,biology.organism_classification ,Pilus ,Cell biology ,03 medical and health sciences ,030104 developmental biology ,Second messenger system ,biology.protein ,Diguanylate cyclase ,Myxococcus xanthus - Abstract
The nucleotide-based second messenger bis-(3'-5')-cyclic dimeric GMP (c-di-GMP) regulates multiple processes in bacteria including cellular motility. The rod-shaped Myxococcus xanthus cells move in the direction of their long axis using two distinct motility systems: type IV pili (T4P)-dependent motility and gliding motility. Manipulation of the c-di-GMP level by expression of either an active, heterologous diguanylate cyclase or an active, heterologous phosphodiesterase causes defects in T4P-dependent motility without affecting gliding motility. As both an increased and a decreased level of c-di-GMP affect T4P-dependent motility, M. xanthus represents a good model system to assess enzyme activity of diguanylate cyclases and phosphodiesterases using T4P-dependent motility as a readout. Here, we describe the assay, which allows correlating diguanylate cyclase and phosphodiesterase activity with T4P-dependent motility in M. xanthus.
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- 2017
407. Motility in blastogregarines (Apicomplexa): Native and drug-induced organisation of Siedleckia nematoides cytoskeletal elements
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Andrea Bardůnek Valigurová, Magdaléna Kováčiková, Gita G. Paskerova, Naděžda Vaškovicová, Andrei Diakin, and Timur G. Simdyanov
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0301 basic medicine ,food.ingredient ,Gliding motility ,Movement ,Cell Membranes ,Motility ,lcsh:Medicine ,Microtubules ,Biochemistry ,03 medical and health sciences ,food ,Contractile Proteins ,Myosin ,Parasite Groups ,Medicine and Health Sciences ,Trophozoites ,Cytoskeleton ,lcsh:Science ,Actin ,Pharmacology ,Inner membrane complex ,Microscopy ,Multidisciplinary ,biology ,lcsh:R ,Biology and Life Sciences ,Proteins ,Drugs ,Cell Biology ,030108 mycology & parasitology ,Actins ,Cell biology ,Cytoskeletal Proteins ,Cell Motility ,030104 developmental biology ,Tubulin ,biology.protein ,Selenidium ,Parasitology ,lcsh:Q ,Cellular Structures and Organelles ,Colchicine ,Apicomplexa ,Research Article - Abstract
Recent studies on motility of Apicomplexa concur with the so-called glideosome concept applied for apicomplexan zoites, describing a unique mechanism of substrate-dependent gliding motility facilitated by a conserved form of actomyosin motor and subpellicular microtubules. In contrast, the gregarines and blastogregarines exhibit different modes and mechanisms of motility, correlating with diverse modifications of their cortex. This study focuses on the motility and cytoskeleton of the blastogregarine Siedleckia nematoides Caullery et Mesnil, 1898 parasitising the polychaete Scoloplos cf. armiger (Muller, 1776). The blastogregarine moves independently on a solid substrate without any signs of gliding motility; the motility in a liquid environment (in both the attached and detached forms) rather resembles a sequence of pendular, twisting, undulation, and sometimes spasmodic movements. Despite the presence of key glideosome components such as pellicle consisting of the plasma membrane and the inner membrane complex, actin, myosin, subpellicular microtubules, micronemes and glycocalyx layer, the motility mechanism of S. nematoides differs from the glideosome machinery. Nevertheless, experimental assays using cytoskeletal probes proved that the polymerised forms of actin and tubulin play an essential role in the S. nematoides movement. Similar to Selenidium archigregarines, the subpellicular microtubules organised in several layers seem to be the leading motor structures in blastogregarine motility. The majority of the detected actin was stabilised in a polymerised form and appeared to be located beneath the inner membrane complex. The experimental data suggest the subpellicular microtubules to be associated with filamentous structures (= cross-linking protein complexes), presumably of actin nature.
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- 2017
408. Comparative Analyses of Transport Proteins Encoded within the Genomes of Bdellovibrio bacteriovorus HD100 and Bdellovibrio exovorus JSS
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Masoud Ahmadzadeh, Gholamreza Salehi Jouzani, Arturo Medrano-Soto, Milton H. Saier, and Fereshteh Heidari Tajabadi
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0301 basic medicine ,Technology ,Physiology ,Gliding motility ,Protein Conformation ,1.1 Normal biological development and functioning ,030106 microbiology ,Bdellovibrio+exovorus<%2Fitalic>%22"> ,Bdellovibrio exovorus Applied Microbiology and Biotechnology ,Biochemistry ,Microbiology ,Article ,Bdellovibrio ,03 medical and health sciences ,Bacterial Proteins ,Underpinning research ,Bdellovibrio exovorus ,Cluster Analysis ,Amino Acid Sequence ,Genome size ,Comparative genomics ,Transporter Classification Database ,Genome ,biology ,Bacterial ,Membrane Transport Proteins ,Bdellovibrio+bacteriovorus<%2Fitalic>%22"> ,Bdellovibrio bacteriovorus Transport proteins ,Biological Transport ,Cell Biology ,Periplasmic space ,Bdellovibrio bacteriovorus ,Biological Sciences ,biology.organism_classification ,Infectious Diseases ,Periplasm ,Generic health relevance ,Efflux ,Carrier Proteins ,Genome, Bacterial ,Predator ,Bacterial Outer Membrane Proteins ,Biotechnology - Abstract
Bdellovibrio, δ-proteobacteria, including B. bacteriovorus (Bba) and B. exovorus (Bex), are obligate predators of other Gram-negative bacteria. While Bba grows in the periplasm of the prey cell, Bex grows externally. We have analyzed and compared the transport proteins of these 2 organisms based on the current contents of the Transporter Classification Database (TCDB; www.tcdb.org). Bba has 103 transporters more than Bex, 50% more secondary carriers, and 3 times as many MFS carriers. Bba has far more metabolite transporters than Bex as expected from its larger genome, but there are 2 times more carbohydrate uptake and drug efflux systems, and 3 times more lipid transporters. Bba also has polyamine and carboxylate transporters lacking in Bex. Bba has more than twice as many members of the Mot-Exb family of energizers, but both may have energizers for gliding motility. They use entirely different types of systems for iron acquisition. Both contain unexpectedly large numbers of pseudogenes and incomplete systems, suggesting that they are undergoing genome size reduction. Interestingly, all 5 outer-membrane receptors in Bba are lacking in Bex. The 2 organisms have similar numbers and types of peptide and amino acid uptake systems as well as protein and carbohydrate secretion systems. The differences observed correlate with and may account, in part, for the different lifestyles of these 2 bacterial predators.
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- 2017
409. Malaria parasite LIMP protein regulates sporozoite gliding motility and infectivity in mosquito and mammalian hosts
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Blandine Franke-Fayard, Andreia Pinto, Friedrich Frischknecht, Gunnar R. Mair, Hirdesh Kumar, Mário da Costa, Vanessa Zuzarte-Luis, Saskia Egarter, Catherine A Moreau, Jorge M. Santos, Chris J. Janse, and Jessica Kehrer
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0301 basic medicine ,Limp ,Gliding motility ,Virulence Factors ,Plasmodium berghei ,QH301-705.5 ,Science ,Protozoan Proteins ,malaria ,Motility ,Biology ,General Biochemistry, Genetics and Molecular Biology ,Epitope ,03 medical and health sciences ,Mice ,parasitic diseases ,medicine ,Gametocyte ,Animals ,Biology (General) ,Cell adhesion ,Infectivity ,Microbiology and Infectious Disease ,General Immunology and Microbiology ,General Neuroscience ,transmission ,Lysosome-Associated Membrane Glycoproteins ,Membrane Proteins ,cell adhesion ,General Medicine ,Cell Biology ,biology.organism_classification ,Virology ,3. Good health ,Cell biology ,Disease Models, Animal ,030104 developmental biology ,Culicidae ,Liver ,Sporozoites ,Medicine ,gliding motility ,Other ,medicine.symptom ,Locomotion ,Research Article - Abstract
Gliding motility allows malaria parasites to migrate and invade tissues and cells in different hosts. It requires parasite surface proteins to provide attachment to host cells and extracellular matrices. Here, we identify the Plasmodium protein LIMP (the name refers to a gliding phenotype in the sporozoite arising from epitope tagging of the endogenous protein) as a key regulator for adhesion during gliding motility in the rodent malaria model P. berghei. Transcribed in gametocytes, LIMP is translated in the ookinete from maternal mRNA, and later in the sporozoite. The absence of LIMP reduces initial mosquito infection by 50%, impedes salivary gland invasion 10-fold, and causes a complete absence of liver invasion as mutants fail to attach to host cells. GFP tagging of LIMP caused a limping defect during movement with reduced speed and transient curvature changes of the parasite. LIMP is an essential motility and invasion factor necessary for malaria transmission. DOI: http://dx.doi.org/10.7554/eLife.24109.001
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- 2017
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410. A Model of Filamentous Cyanobacteria Leading to Reticulate Pattern Formation
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Jaap A. Kaandorp, Carlos Tamulonis, and Computational Science Lab (IVI, FNWI)
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computational modeling ,Gliding motility ,Ecology ,Microorganism ,Paleontology ,Pattern formation ,Model parameters ,Biology ,Filamentous cyanobacteria ,Article ,General Biochemistry, Genetics and Molecular Biology ,Trichome ,stromatolites ,Reticulate ,Space and Planetary Science ,Evolutionary biology ,filamentous cyanobacteria ,lcsh:Q ,Microbial mat ,lcsh:Science ,Ecology, Evolution, Behavior and Systematics - Abstract
The filamentous cyanobacterium, Pseudanabaena, has been shown to produce reticulate patterns that are thought to be the result of its gliding motility. Similar fossilized structures found in the geological record constitute some of the earliest signs of life on Earth. It is difficult to tie these fossils, which are billions of years old, directly to the specific microorganisms that built them. Identifying the physicochemical conditions and microorganism properties that lead microbial mats to form macroscopic structures can lead to a better understanding of the conditions on Earth at the dawn of life. In this article, a cell-based model is used to simulate the formation of reticulate patterns in cultures of Pseudanabaena. A minimal system of long and flexible trichomes capable of gliding motility is shown to be sufficient to produce stable patterns consisting of a network of streams. Varying model parameters indicate that systems with little to no cohesion, high trichome density and persistent movement are conducive to reticulate pattern formation, in conformance with experimental observations.
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- 2014
411. Potential Role of Flavobacterial Gliding-Motility and Type IX Secretion System Complex in Root Colonization and Plant Defense
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Yigal Elad, Eddie Cytryn, Omer Frenkel, and Max Kolton
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Physiology ,Gliding motility ,Mutant ,Flavobacterium ,Plant Roots ,Bacterial Adhesion ,Microbiology ,Bacterial Proteins ,Solanum lycopersicum ,Actinomycetales ,Botany ,Plant defense against herbivory ,Plant Immunity ,Secretion ,Colonization ,Bacterial Secretion Systems ,Soil Microbiology ,Plant Diseases ,Rhizosphere ,biology ,General Medicine ,biology.organism_classification ,Phenotype ,Mutation ,Seeds ,Agronomy and Crop Science ,Soil microbiology ,Clavibacter michiganensis - Abstract
Members of the Flavobacterium genus are often highly abundant in the rhizosphere. Nevertheless, the physiological characteristics associated with their enhanced rhizosphere competence are currently an enigma. Flavobacteria possess a unique gliding-motility complex that is tightly associated with a recently characterized Bacteroidetes-specific type IX protein secretion system, which distinguishes them from the rest of the rhizosphere microbiome. We hypothesize that proper functionality of this complex may confer a competitive advantage in the rhizosphere. To test this hypothesis, we constructed mutant and complement root-associated flavobacterial variants with dysfunctional secretion and gliding motility, and tested them in a series of in planta experiments. These mutants demonstrated significantly lower rhizosphere persistence (approximately 10-fold), plant root colonization (approximately fivefold), and seed adhesion capacity (approximately sevenfold) than the wild-type strains. Furthermore, the biocontrol capacity of the mutant strain toward foliar-applied Clavibacter michiganensis was significantly impaired relative to the wild-type strain, suggesting a role of the gliding and secretion complex in plant protection. Collectively, these results provide an initial link between the high abundance of flavobacteria in the rhizosphere and their unique physiology, indicating that the flavobacterial gliding-motility and secretion complex may play a central role in root colonization and plant defense.
- Published
- 2014
412. Identification and characterization ofToxoplasma SIP, a conserved apicomplexan cytoskeleton protein involved in maintaining the shape, motility and virulence of the parasite
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Boris Striepen, Cyrille Claudet, Maryse Lebrun, Maria E. Francia, Gaelle Lentini, Jean-François Dubremetz, Marie Kong-Hap, and Hiba El Hajj
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Inner membrane complex ,biology ,Gliding motility ,Immunology ,Virulence ,Motility ,biology.organism_classification ,Microbiology ,Cell biology ,Apicomplexa ,Cytoplasm ,Virology ,parasitic diseases ,Subpellicular network ,Cytoskeleton - Abstract
Summary Apicomplexa possess a complex pellicle that is composed of a plasma membrane and a closely apposed inner membrane complex (IMC) that serves as a support for the actin-myosin motor required for motility and host cell invasion. The IMC consists of longitudinal plates of flattened vesicles, fused together and lined on the cytoplasmic side by a subpellicular network of intermediate filament-like proteins. The spatial organization of the IMC has been well described by electron microscopy, but its composition and molecular organization is largely unknown. Here, we identify a novel protein of the IMC cytoskeletal network in Toxoplasma gondii, called TgSIP, and conserved among apicomplexan parasites. To finely pinpoint the localization of TgSIP, we used structured illumination super-resolution microscopy and revealed that it likely decorates the transverse sutures of the plates and the basal end of the IMC. This suggests that TgSIP might contribute to the organization or physical connection among the different components of the IMC. We generated a T.gondii SIP deletion mutant and showed that parasites lacking TgSIP are significantly shorter than wild-type parasites and show defects in gliding motility, invasion and reduced infectivity in mice.
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- 2014
413. Multimotor Transport in a System of Active and Inactive Kinesin-1 Motors
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Rui Ma, Stefan Diez, Lara Scharrel, René Schneider, and Frank Jülicher
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Cytoplasmic dynein ,Gliding motility ,Biophysics ,Motility ,Nanotechnology ,Biology ,Motor protein ,medicine.anatomical_structure ,Microtubule ,medicine ,Axoplasmic transport ,Kinesin ,Axon - Abstract
Long-range directional transport in cells is facilitated by microtubule-based motor proteins. One example is transport in a nerve cell, where small groups of motor proteins, such as kinesins and cytoplasmic dynein, work together to ensure the supply and clearance of cellular material along the axon. Defects in axonal transport have been linked to Alzheimer’s and other neurodegenerative diseases. However, it is not known in detail how multimotor-based cargo transport is impaired if a fraction of the motors are defective. To mimic impaired multimotor transport in vitro, we performed gliding motility assays with varying fractions of active kinesin-1 motors and inactive kinesin-1 motor mutants. We found that impaired transport manifests in multiple motility regimes: 1), a fast-motility regime characterized by gliding at velocities close to the single-molecule velocity of the active motors; 2), a slow-motility regime characterized by gliding at close-to zero velocity or full stopping; and 3), a regime in which fast and slow motilities coexist. Notably, the transition from the fast to the slow regime occurred sharply at a threshold fraction of active motors. Based on single-motor parameters, we developed a stochastic model and a mean-field theoretical description that explain our experimental findings. Our results demonstrate that impaired multimotor transport mostly occurs in an either/or fashion: depending on the ratio of active to inactive motors, transport is either performed at close to full speed or is out of action.
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- 2014
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414. Chlamydomonas reinhardtii as a model for flagellar assembly
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Karl F. Lechtreck
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Axoneme ,Ciliopathy ,biology ,Gliding motility ,Chemistry ,Intraflagellar transport ,Cilium ,medicine ,Chlamydomonas reinhardtii ,biology.organism_classification ,medicine.disease ,Cell biology - Published
- 2014
415. Assessment of phosphorylation inToxoplasmaglideosome assembly and function
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Pushkar Sharma, Dominique Soldati-Favre, Jean-Baptiste Marq, Damien Jacot, and Karine Frénal
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Inner membrane complex ,Myosin light-chain kinase ,Gliding motility ,Immunology ,Wild type ,Biology ,Microbiology ,Cell biology ,Biochemistry ,Virology ,Myosin ,Molecular motor ,Phosphorylation ,Integral membrane protein - Abstract
Members of the phylum Apicomplexa possess a highly conserved molecular motor complex anchored in the parasite pellicle and associated with gliding motility, invasion and egress from infected cells. This machinery, called the glideosome, is structured around the acylated gliding-associated protein GAP45 that recruits the motor complex composed of myosin A and two associated myosin light chains (TgMLC1 and TgELC1). This motor is presumably firmly anchored to the inner membrane complex underneath the plasma membrane via an interaction with two integral membrane proteins, GAP50 and GAP40. To determine if the previously mapped phosphorylation sites on TgGAP45 and TgMLC1 have a direct significance for glideosome assembly and function, a series of phospho-mimetic and phospho-null mutants were generated. Neither the overexpression nor the allelic replacement of TgMLC1 with phospho-mutants impacted on glideosome assembly and parasite motility. TgGAP45 phosphorylation mutants were functionally investigated using a complementation strategy in a TgGAP45 inducible knockout background. The loss of interaction with TgGAP50 by one previously reported GAP45-mutant appeared to depend only on the presence of a remaining competing wild type copy of TgGAP45. Accordingly, this mutant displayed no phenotype in complementation experiments. Unexpectedly, GAP45 lacking the region encompassing the cluster of twelve phosphorylation sites did not impact on its dual function in motor recruitment and pellicle integrity. Despite the extensive phosphorylation of TgMLC1 and TgGAP45, this post-translational modification does not appear to be critical for the assembly and function of the glideosome.
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- 2014
416. Calcium dynamics ofPlasmodium bergheisporozoite motility
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Sabine Thiberge, Robert Ménard, Allison F. Carey, Daniel Y. Bargieri, Mirko Singer, Rogerio Amino, and Friedrich Frischknecht
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0303 health sciences ,biology ,030306 microbiology ,Gliding motility ,Immunology ,chemistry.chemical_element ,Motility ,Calcium ,biology.organism_classification ,Microbiology ,3. Good health ,Intracellular ca ,Cell biology ,03 medical and health sciences ,chemistry ,Calcium dynamics ,Cytoplasm ,Virology ,parasitic diseases ,Parasite hosting ,Plasmodium berghei ,human activities ,030304 developmental biology - Abstract
Summary Calcium is a key signalling molecule in apicom- plexan parasites and plays an important role in diverse processes including gliding motility. Gliding is essential for the malaria parasite to migrate from the skin to the liver as well as to invade host tissues and cells. Here we investigated the dynamics of intracellular Ca 2+ in the motility of
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- 2014
417. Recombinant production, purification and crystallization of theToxoplasma gondiicoronin WD40 domain
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Inari Kursula and Juha P. Kallio
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Gliding motility ,Molecular Sequence Data ,Biophysics ,Coronin ,Crystallography, X-Ray ,Biochemistry ,Structural Biology ,parasitic diseases ,Myosin ,Genetics ,Amino Acid Sequence ,Actin-binding protein ,Peptide sequence ,Actin ,Sequence Homology, Amino Acid ,biology ,Microfilament Proteins ,Toxoplasma gondii ,Condensed Matter Physics ,biology.organism_classification ,Actin cytoskeleton ,Recombinant Proteins ,Protein Structure, Tertiary ,Cell biology ,Crystallization Communications ,biology.protein ,Crystallization ,Toxoplasma - Abstract
Toxoplasma gondiiis one of the most widely spread parasitic organisms in the world. Together with other apicomplexan parasites, it utilizes a special actin–myosin motor for its cellular movement, called gliding motility. This actin-based process is regulated by a small set of actin-binding proteins, which in Apicomplexa comprises only 10–15 proteins, compared with >150 in higher eukaryotes. Coronin is a highly conserved regulator of the actin cytoskeleton, but its functions, especially in parasites, have remained enigmatic. Coronins consist of an N-terminal actin-binding β-propeller WD40 domain, followed by a conserved region, and a C-terminal coiled-coil domain implicated in oligomerization. Here, the WD40 domain and the conserved region of coronin fromT. gondiiwere produced recombinantly and crystallized. A single-wavelength diffraction data set was collected to a resolution of 1.65 Å. The crystal belonged to the orthorhombic space groupC2221, with unit-cell parametersa= 55.13,b= 82.51,c= 156.98 Å.
- Published
- 2014
418. Thehmpchemotaxis cluster regulates gliding in the filamentous cyanobacteriumNostoc punctiforme
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Loralyn M. Cozy and Sean M. Callahan
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animal structures ,biology ,Gliding motility ,musculoskeletal, neural, and ocular physiology ,Nostoc punctiforme ,Motility ,Chemotaxis ,Flagellum ,biology.organism_classification ,Microbiology ,Pilus ,Cell biology ,stomatognathic system ,Hormogonium ,Molecular Biology ,Bacteria - Abstract
Summary Many bacteria are capable of movement over surfaces without flagella or pili; they glide. Nostoc punctiforme is a cyanobacterium that differentiates specialized gliding filaments called hormogonia, but the mechanism underlying their movement is currently unknown. Risser et al. characterize the hormogonia motility and polysaccharide (hmp) locus that encodes proteins homologous to well-studied chemotaxis systems. All but one of the genes in the locus were required for gliding motility and each protein localized as a ring near the cell junction. One protein, the CheA homologue HmpE, was capable of autophosphorylation and phosphotransfer to the CheY homologue HmpB. This study reveals the hmp locus as an important regulator of gliding and highlights N. punctiforme as a model for understanding gliding motility in a complex multicellular bacterium.
- Published
- 2014
419. Genetic characterization of thehmplocus, a chemotaxis-like gene cluster that regulates hormogonium development and motility inNostoc punctiforme
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William G. Chew, John C. Meeks, and Douglas D. Risser
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Genetics ,Pore complex ,animal structures ,biology ,Gliding motility ,Nostoc punctiforme ,Mutant ,Motility ,Locus (genetics) ,biology.organism_classification ,Microbiology ,Cell biology ,Gene cluster ,Hormogonium ,Molecular Biology - Abstract
Summary Filamentous cyanobacteria are capable of gliding motility, but the mechanism of motility is not well defined. Here we present a detailed characterization of the hmp locus from Nostoc punctiforme, which encodes chemotaxis-like proteins. Deletions of hmpB, C, D and E abolished differentiation of hormogonia under standard growth conditions, but, upon addition of a symbiotic partner exudate, the mutant strains differentiated hormogonium-like filaments that lacked motility and failed to secrete hormogonium specific polysaccharide. The hmp locus is expressed as two transcripts, one originating 5′ of hmpA and encompassing the entire hmp locus, and the other 5′ of hmpB and encompassing hmpBCDE. The CheA-like HmpE donates phosphate to its own C-terminal receiver domain, and to the CheY-like HmpB, but not to the PatA family CheY-like HmpA. A GFP-tagged variant of each hmp locus protein localized to a ring adjacent to the septum on each end of the rod-shaped cell. Immunofluorescence demonstrated that PilA localizes to a ring at the junction between cells. The phenotype of the deletion strains, and the localization of the Hmp proteins and the putative PilA protein to rings at the cell junctions are consistent with the hypothesis that these proteins are part of the junctional pore complex observed in a number of filamentous cyanobacteria.
- Published
- 2014
420. Plasmodium berghei Sporozoites Acquire Virulence and Immunogenicity during Mosquito Hemocoel Transit
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Georgina N. Montagna, Kai Matuschewski, and Yuko Sato
- Subjects
Carcinoma, Hepatocellular ,Plasmodium berghei ,Gliding motility ,Immunology ,Protozoan Proteins ,Virulence ,Biology ,Microbiology ,Plasmodium ,Salivary Glands ,Mice ,Cell Line, Tumor ,parasitic diseases ,medicine ,Animals ,Humans ,Infectivity ,Attenuated vaccine ,Salivary gland ,Immunogenicity ,fungi ,biology.organism_classification ,Virology ,Insect Vectors ,Malaria ,Mice, Inbred C57BL ,Culicidae ,Infectious Diseases ,medicine.anatomical_structure ,Liver ,Sporozoites ,Antibody Formation ,Female ,Parasitology ,Fungal and Parasitic Infections - Abstract
Malaria is a vector-borne disease caused by the single-cell eukaryote Plasmodium . The infectious parasite forms are sporozoites, which originate from midgut-associated oocysts, where they eventually egress and reach the mosquito hemocoel. Sporozoites actively colonize the salivary glands in order to be transmitted to the mammalian host. Whether residence in the salivary glands provides distinct and vital cues for the development of infectivity remains unsolved. In this study, we systematically compared the infectivity of Plasmodium berghei sporozoites isolated from the mosquito hemocoel and salivary glands. Hemocoel sporozoites display a lower proportion of gliding motility but develop into liver stages when added to cultured hepatoma cells or after intravenous injection into mice. Mice infected by hemocoel sporozoites had blood infections similar to those induced by sporozoites liberated from salivary glands. These infected mice display indistinguishable systemic inflammatory cytokine responses and develop experimental cerebral malaria. When used as metabolically active, live attenuated vaccine, hemocoel sporozoites elicit substantial protection against sporozoite challenge infections. Collectively, these findings show that salivary gland colonization does not influence parasite virulence in the mammalian host when sporozoites are administered intravenously. This conclusion has important implications for in vitro sporozoite production and manufacturing of whole-sporozoite vaccines.
- Published
- 2014
421. Toxoplasma aldolase is required for metabolism but dispensable for host-cell invasion
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L. David Sibley and Bang Shen
- Subjects
DNA, Complementary ,Gliding motility ,Blotting, Western ,Fructose-bisphosphate aldolase ,Motility ,Enzyme-Linked Immunosorbent Assay ,Biology ,Models, Biological ,Host-Parasite Interactions ,Microneme ,Gene Knockout Techniques ,Tandem Mass Spectrometry ,Fructose-Bisphosphate Aldolase ,Multidisciplinary ,Aldolase A ,Biological Sciences ,Apical membrane ,Transmembrane protein ,Bacterial adhesin ,Glucose ,Microscopy, Fluorescence ,Biochemistry ,biology.protein ,Energy Metabolism ,Toxoplasma ,Chromatography, Liquid ,Plasmids - Abstract
Gliding motility and host-cell invasion by apicomplexan parasites depend on cell-surface adhesins that are translocated via an actin-myosin motor beneath the membrane. The current model posits that fructose-1,6-bisphosphate aldolase (ALD) provides a critical link between the cytoplasmic tails of transmembrane adhesins and the actin-myosin motor. Here we tested this model using the Toxoplasma gondii apical membrane protein 1 (TgAMA1), which binds to aldolase in vitro. TgAMA1 cytoplasmic tail mutations that disrupt ALD binding in vitro showed no correlation with host-cell invasion, indicating this interaction is not essential. Furthermore, ALD-depleted parasites were impaired when grown in glucose, yet they showed normal gliding and invasion in glucose-free medium. Depletion of ALD in the presence of glucose led to accumulation of fructose-1,6-bisphosphate, which has been associated with toxicity in other systems. Finally, TgALD knockout parasites and an ALD mutant that specifically disrupts adhesin binding in vitro also supported normal invasion when cultured in glucose-free medium. Taken together, these results suggest that ALD is primarily important for energy metabolism rather than interacting with microneme adhesins, challenging the current model for apicomplexan motility and invasion.
- Published
- 2014
422. Imaging mosquito transmission of Plasmodium sporozoites into the mammalian host: Immunological implications
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Jerome P. Vanderberg
- Subjects
Mammals ,Microscopy ,Plasmodium ,Gliding motility ,Anopheles ,Antibodies, Protozoan ,Biology ,biology.organism_classification ,Virology ,Malaria ,Cell biology ,Circumsporozoite protein ,Infectious Diseases ,Lymphatic system ,Immune system ,medicine.anatomical_structure ,Dermis ,Sporozoites ,Immunity ,parasitic diseases ,medicine ,Animals ,Parasitology - Abstract
The malaria infection is initiated in mammals by injection of the sporozoite stage of the parasite through the bite of Plasmodium-infected, female Anopheles mosquitoes. Sporozoites are injected into extravascular portions of the skin while the mosquito is probing for a blood source. Sporozoite gliding motility allows them to locate and penetrate blood vessels of the dermis or subcutaneous tissues; once in the blood, they reach the liver, within which they continue their development. Some of the injected parasites invade dermal lymph vessels and travel to the proximal draining lymphatic node, where they interact with host immunocytes. The host responds to viable or attenuated sporozoites with antibodies directed against the immunodominant circumsporozoite protein (CSP), as well as against other sporozoite proteins. These CSP antibodies can inhibit the numbers of sporozoites injected by mosquitoes and the motility of those injected into the skin. This first phase of the immune response is followed by cell-mediated immunity involving CD8 T-cells directed against the developing liver stage of the parasite. This review discusses the early history of imaging studies, and focuses on the role that imaging has played in enabling a better understanding of both the induction and effector functions of the immune responses against sporozoites.
- Published
- 2014
423. Flavobacterium crassostreae sp. nov., isolated from Pacific oyster
- Author
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Sungmi Choi, Eunji Kim, Hana Yi, and Su Kyoung Shin
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0106 biological sciences ,0301 basic medicine ,DNA, Bacterial ,Gliding motility ,Biology ,010603 evolutionary biology ,01 natural sciences ,Microbiology ,Flavobacterium ,03 medical and health sciences ,chemistry.chemical_compound ,stomatognathic system ,RNA, Ribosomal, 16S ,Republic of Korea ,Animals ,Crassostrea ,Genome size ,Ecology, Evolution, Behavior and Systematics ,Phylogeny ,Base Composition ,Strain (chemistry) ,Phosphatidylethanolamines ,fungi ,Fatty Acids ,General Medicine ,Sequence Analysis, DNA ,Pacific oyster ,equipment and supplies ,16S ribosomal RNA ,biology.organism_classification ,Bacterial Typing Techniques ,030104 developmental biology ,chemistry ,bacteria ,DNA ,Flavobacterium crassostreae - Abstract
A yellow, rod-shaped, Gram-reaction-negative bacterial strain, designated LPB0076T, was isolated from a Pacific oyster. Results of 16S rRNA gene sequence analyses indicated that the strain represented a member of the genus Flavobacterium . It had the highest sequence similarity to the type strains of Flavobacterium frigidarium (97.6 %) and Flavobacterium omnivorum (97.0 %), and its similarities with all other species of the genus Flavobacterium were below 97.0 %. Its genome size (3.02 Mb), DNA G+C content (36.0 mol%), predominant cellular fatty acids (anteiso-C15 : 0, iso-C15 : 0 and C16 : 1ω7c and/or C17 : 1ω6c), and major polar lipid (phosphatidylethanolamine) were similar to those described previously for members of the genus Flavobacterium . In contrast, a number of phenotypic characteristics, including the inability to grow microaerophilically, absence of flexirubin-type pigments and gliding motility and differences in enzymatic reactions, clearly distinguished LPB0076T from other species of the genus Flavobacterium . The polyphasic data presented in this study indicate that this isolate should be classified as representing a novel species of the genus Flavobacterium . The name Flavobacterium crassostreae sp. nov. is therefore proposed for the isolate, with the type strain being LPB0076T (=KACC 18706T=JCM 31219T).
- Published
- 2016
424. Roseovarius confluentis sp. nov., isolated from estuary sediment
- Author
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Che Ok Jeon, Xiaomeng Jia, Kyunghwa Baek, Hye Hee Jeon, Sang-Ho Choi, Baolei Jia, and Hye Rim Kim
- Subjects
0106 biological sciences ,0301 basic medicine ,DNA, Bacterial ,Geologic Sediments ,Gliding motility ,Sequence analysis ,Ubiquinone ,010603 evolutionary biology ,01 natural sciences ,Microbiology ,03 medical and health sciences ,Phylogenetics ,RNA, Ribosomal, 16S ,Republic of Korea ,Seawater ,Rhodobacteraceae ,Ecology, Evolution, Behavior and Systematics ,Phospholipids ,Phylogeny ,Oxidase test ,Base Composition ,Phylogenetic tree ,biology ,Fatty Acids ,Alphaproteobacteria ,General Medicine ,Sequence Analysis, DNA ,Ribosomal RNA ,biology.organism_classification ,16S ribosomal RNA ,Bacterial Typing Techniques ,030104 developmental biology ,lipids (amino acids, peptides, and proteins) ,Estuaries - Abstract
A Gram-stain-negative and strictly aerobic bacterium, designated strain SAG6T, was isolated from estuary sediment in South Korea. Cells of strain SAG6T were found to be oxidase- and catalase-positive rods with gliding motility. Cell growth was observed at 15–40 °C (optimum 30 °C), at pH 6.5–10.0 (optimum pH 7.0) and in the presence of 0.5–13.0 % (w/v) NaCl (optimum 2.0 %). Ubiquinone-10 was the only detected respiratory quinone and summed feature 8 (comprising C18 : 1ω7c/C18 : 1ω6c), C16 : 0, C18 : 1ω7c 11-methyl and C12 : 0 were the major fatty acids identified (>5 % of the total fatty acids). The polar lipids of strain SAG6T consisted of phosphatidylcholine, phosphatidylglycerol, diphosphatidylglycerol, an unidentified aminolipid and two unidentified lipids. The G+C content of the genomic DNA was 66.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain SAG6T formed a tight phyletic lineage within the genus Roseovarius . Strain SAG6T was most closely related to Roseovarius indicus B108T with 97.6 % 16S rRNA gene sequence similarity. Based on phenotypic, chemotaxonomic and molecular features, strain SAG6T clearly represents a novel species of the genus Roseovarius , for which the name Roseovarius confluentis sp. nov. is proposed. The type strain is SAG6T (=KACC 18598T=JCM 31541T).
- Published
- 2016
425. Structures related to attachment and motility in the marine eugregarine Cephaloidophora cf. communis (Apicomplexa)
- Author
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Andrei Diakin, Andrea Bardůnek Valigurová, Timur G. Simdyanov, and Magdaléna Kováčiková
- Subjects
0301 basic medicine ,biology ,Gliding motility ,Thoracica ,Motility ,Anatomy ,Motor Activity ,biology.organism_classification ,Microbiology ,Cell biology ,Host-Parasite Interactions ,Apicomplexa ,03 medical and health sciences ,030104 developmental biology ,Tubulin ,Balanus balanus ,Myosin ,biology.protein ,Parasite hosting ,Animals ,Actin - Abstract
Gregarines represent a highly diversified group of ancestral apicomplexans, with various modes of locomotion and host-parasite interactions. The eugregarine parasite of the barnacle Balanus balanus, Cephaloidophora cf. communis, exhibits interesting organisation of its attachment apparatus along with unique motility modes. The pellicle covered gregarine is arranged into longitudinal epicytic folds. The epimerite is separated from the protomerite by a septum consisting of tubulin-rich filamentous structures and both are packed with microneme-like structures suggestive of their function in the production of adhesives important for attachment and secreted through the abundant epimerite pores. Detached trophozoites and gamonts are capable of gliding motility, enriched by jumping and rotational movements with rapid changes in gliding direction and cell flexions. Actin in its polymerised form (F-actin) is distributed throughout the entire gregarine, while myosin, detected in the cortical region of the cell, follows the pattern of the epicytic folds. Various motility modes exhibited by individuals of C. cf. communis, together with significant changes in their cell shape during locomotion, are not concordant with the gliding mechanisms generally described in apicomplexan zoites and indicate that additional structures must be involved (e.g. two 12-nm filaments; the specific dentate appearance of internal lamina inside the epicytic folds).
- Published
- 2016
426. Parasite actin in action
- Author
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Stella M. Hurtley
- Subjects
Multidisciplinary ,biology ,Gliding motility ,Transgene ,macromolecular substances ,Vacuole ,biology.organism_classification ,Filamentous actin ,Plasmodium ,Cell biology ,parasitic diseases ,Organelle ,Parasite hosting ,Actin - Abstract
Cell Biology In apicomplexan parasites, such as Plasmodium or Toxoplasma species, the major function of parasite filamentous actin (F-actin) was thought to be limited to gliding motility and host cell invasion. Using live-cell imaging, Periz et al. studied transgenic parasites labeled with anti-actin camel antibodies fused to fluorescent markers. They found that Toxoplasma parasites within host cell vacuoles formed an F-actin network that connected individual parasites and was required for recycling of maternal organelles. Using similar technologies, Del Rosario et al. investigated the F-actin dynamics of apicomplexan parasites during host cell invasion. Superresolution microscopy revealed that invading parasites have perinuclear F-actin that eases passage of the parasite nucleus into the host cell. Thus, apicomplexan F-actin can form highly dynamic filaments in vivo that fulfill multiple functions during parasite development and invasion. Nat. Commun. 10 , 4183 (2019); EMBO Rep. 2019 , e48896 (2019).
- Published
- 2019
427. Malaria transmission through the mosquito requires the function of the OMD protein
- Author
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Patricia A. G. C. Silva, Leandro Lemgruber, Chiara Currà, Jessica Kehrer, Gunnar R. Mair, Marta Ponzi, Lucia Bertuccini, Inga Siden-Kiamos, Tomasino Pace, Friedrich Frischknecht, and Fabiana Superti
- Subjects
Plasmodium ,Plasmodium berghei ,Physiology ,Gliding motility ,Mutant ,Protozoan Proteins ,Artificial Gene Amplification and Extension ,Gametocytes ,Polymerase Chain Reaction ,Mice ,Animal Cells ,Medicine and Health Sciences ,Parasite hosting ,Fluorescent Antibody Technique, Indirect ,Protozoans ,0303 health sciences ,Multidisciplinary ,Reverse Transcriptase Polymerase Chain Reaction ,Malarial Parasites ,Eukaryota ,Body Fluids ,3. Good health ,Cell biology ,Blood ,Gene Knockdown Techniques ,Medicine ,Female ,Cellular Types ,Anatomy ,Research Article ,Science ,Motility ,DNA construction ,Biology ,Research and Analysis Methods ,03 medical and health sciences ,Anopheles ,Parasite Groups ,parasitic diseases ,Parasitic Diseases ,medicine ,Gametocyte ,Animals ,Molecular Biology Techniques ,Molecular Biology ,030304 developmental biology ,030306 microbiology ,Host (biology) ,Organisms ,Oocysts ,Biology and Life Sciences ,Cell Biology ,medicine.disease ,Parasitic Protozoans ,Malaria ,Germ Cells ,Plasmid Construction ,Microscopy, Electron, Scanning ,Parasitology ,Apicomplexa ,Function (biology) - Abstract
Ookinetes, one of the motile and invasive forms of the malaria parasite, rely on gliding motility in order to establish an infection in the mosquito host. Here we characterize the protein PBANKA_0407300 which is conserved in the Plasmodium genus but lacks significant similarity to proteins of other eukaryotes. It is expressed in gametocytes and throughout the invasive mosquito stages of P. berghei, but is absent from asexual blood stages. Mutants lacking the protein developed morphologically normal ookinetes that were devoid of productive motility although some stretching movement could be detected. We therefore named the protein Ookinete Motility Deficient (OMD). Several key factors known to be involved in motility however were normally expressed and localized in the mutant. Importantly, the mutant failed to establish an infection in the mosquito which resulted in a total malaria transmission blockade.
- Published
- 2019
428. Functional antibodies against Plasmodium falciparum sporozoites are associated with a longer time to qPCR-detected infection among schoolchildren in Burkina Faso
- Author
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Robert W. Sauerwein, Issiaka Soulama, Alfred B. Tiono, Bronner P. Gonçalves, Alphonse Ouedraogo, Lynn Grignard, Teun Bousema, Kjerstin Lanke, Issa Nebie, Chris Drakeley, Koen J. Dechering, Marije C. Behet, Judith M. Bolscher, and Aissata Barry
- Subjects
0301 basic medicine ,biology ,Gliding motility ,030231 tropical medicine ,Medicine (miscellaneous) ,Plasmodium falciparum ,medicine.disease ,biology.organism_classification ,General Biochemistry, Genetics and Molecular Biology ,3. Good health ,Circumsporozoite protein ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Immune system ,Antigen ,Immunity ,parasitic diseases ,Immunology ,medicine ,biology.protein ,Antibody ,Malaria - Abstract
Background: Individuals living in malaria-endemic regions develop immunity against severe malaria, but it is unclear whether immunity against pre-erythrocytic stages that blocks initiation of blood-stage infection after parasite inoculation develops following continuous natural exposure. Methods: We cleared schoolchildren living in an area (health district of Saponé, Burkina Faso) with highly endemic seasonal malaria of possible sub-patent infections and examined them weekly for incident infections by nested PCR. Plasma samples collected at enrolment were used to quantify antibodies to the pre-eryhrocytic-stage antigens circumsporozoite protein (CSP) and Liver stage antigen 1 (LSA-1). In vitro sporozoite gliding inhibition and hepatocyte invasion inhibition by naturally acquired antibodies were assessed using Plasmodium falciparum NF54 sporozoites. Associations between antibody responses, functional pre-erythrocytic immunity phenotypes and time to infection detected by 18S quantitative PCR were studied. Results: A total of 51 children were monitored. Anti-CSP antibody titres showed a positive association with sporozoite gliding motility inhibition (PIn vitro hepatocyte invasion was inhibited by naturally acquired antibodies (median inhibition, 19.4% [IQR 15.2-40.9%]), and there were positive correlations between invasion inhibition and gliding inhibition (P=0.005, Spearman’s ρ=0.67) and between invasion inhibition and CSP-specific antibodies (P=0.002, Spearman’s ρ=0.76). Survival analysis indicated longer time to infection in individuals displaying higher-than-median sporozoite gliding inhibition activity (P=0.01), although this association became non-significant after adjustment for blood-stage immunity (P = 0.06). Conclusions: In summary, functional antibodies against the pre-erythrocytic stages of malaria infection are acquired in children who are repeatedly exposed to Plasmodium parasites. This immune response does not prevent them from becoming infected during a malaria transmission season, but might delay the appearance of blood stage parasitaemia. Our approach could not fully separate the effects of pre-erythrocytic-specific and blood-stage-specific antibody-mediated immune responses in vivo; epidemiological studies powered and designed to address this important question should become a research priority.
- Published
- 2019
429. Biogenesis and secretion of micronemes inToxoplasma gondii
- Author
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David Jean Dubois and Dominique Soldati-Favre
- Subjects
Gliding motility ,Immunology ,Membrane Fusion ,Microbiology ,Exocytosis ,Host-Parasite Interactions ,Apicomplexa ,Microneme ,03 medical and health sciences ,Virology ,parasitic diseases ,Animals ,Humans ,Secretion ,030304 developmental biology ,Organelles ,ddc:616 ,0303 health sciences ,Organelle Biogenesis ,Rhoptry ,biology ,Perforin ,030306 microbiology ,Effector ,Cell Membrane ,biology.organism_classification ,3. Good health ,Cell biology ,Toxoplasma ,Biogenesis ,Peptide Hydrolases ,Signal Transduction - Abstract
One of the hallmarks of the parasitic phylum of Apicomplexa is the presence of highly specialised, apical secretory organelles, called the micronemes and rhoptries that play critical roles in ensuring survival and dissemination. Upon exocytosis, the micronemes release adhesin complexes, perforins, and proteases that are crucially implicated in egress from infected cells, gliding motility, migration across biological barriers, and host cell invasion. Recent studies on Toxoplasma gondii and Plasmodium species have shed more light on the signalling events and the machinery that trigger microneme secretion. Intracellular cyclic nucleotides, calcium level, and phosphatidic acid act as key mediators of microneme exocytosis, and several downstream effectors have been identified. Here, we review the key steps of microneme biogenesis and exocytosis, summarising the still fractal knowledge at the molecular level regarding the fusion event with the parasite plasma membrane.
- Published
- 2019
430. Structure-Guided Identification of Resistance Breaking Antimalarial N‑Myristoyltransferase Inhibitors
- Author
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Jeremy N. Burrows, Sally Lyons-Abbott, Anthony A. Holder, Ellen Knuepfer, Chun-Wa Chung, Anja C. Schlott, Roger Bonnert, Edward W. Tate, David Charter, Andrew Simon Bell, Olivia Coburn-Flynn, Alexandra R. Reers, Peter J. Myler, Judith L. Green, Brice Campo, David A. Fidock, Stephen J. Mayclin, and Bart Staker
- Subjects
Plasmodium ,Gliding motility ,Clinical Biochemistry ,Drug resistance ,Protein lipidation ,01 natural sciences ,Biochemistry ,DESIGN ,Drug Discovery ,BINDING ,Transferase ,Enzyme Inhibitors ,Malaria, Falciparum ,chemistry.chemical_classification ,biology ,PLASMODIUM-FALCIPARUM ,myristoylation ,DRUG TARGET ,genetic manipulation ,3. Good health ,GENOME ,Drug development ,Molecular Medicine ,antimalarial target ,Life Sciences & Biomedicine ,Biochemistry & Molecular Biology ,crystal structure ,Plasmodium falciparum ,malaria ,Polymorphism, Single Nucleotide ,Article ,Antimalarials ,Humans ,Amino Acid Sequence ,PARASITE ,Molecular Biology ,N-myristoyltransferase ,Myristoylation ,Pharmacology ,Science & Technology ,010405 organic chemistry ,biology.organism_classification ,drug resistance development ,0104 chemical sciences ,Enzyme ,chemistry ,post-translational modification ,DISCOVERY ,protein lipidation ,Protein Processing, Post-Translational ,HUMAN MALARIA ,Acyltransferases - Abstract
Summary The attachment of myristate to the N-terminal glycine of certain proteins is largely a co-translational modification catalyzed by N-myristoyltransferase (NMT), and involved in protein membrane-localization. Pathogen NMT is a validated therapeutic target in numerous infectious diseases including malaria. In Plasmodium falciparum, NMT substrates are important in essential processes including parasite gliding motility and host cell invasion. Here, we generated parasites resistant to a particular NMT inhibitor series and show that resistance in an in vitro parasite growth assay is mediated by a single amino acid substitution in the NMT substrate-binding pocket. The basis of resistance was validated and analyzed with a structure-guided approach using crystallography, in combination with enzyme activity, stability, and surface plasmon resonance assays, allowing identification of another inhibitor series unaffected by this substitution. We suggest that resistance studies incorporated early in the drug development process help selection of drug combinations to impede rapid evolution of parasite resistance., Graphical Abstract, Highlights • Discovery of a mutant offering resistance against P. falciparum NMT inhibitor IMP-1002 • Structural basis of the mechanism of resistance revealed by X-ray crystallography • Genetic and chemical validation of resistance using CRISPR-Cas9 and enzyme assays • Crystal structures of PvNMT[G386E] with IMP-1002 versus DDD85646, overcoming resistance, Structural studies of N-myristoyltransferase (NMT) of the malaria parasite Plasmodium falciparum combined with inhibitors decipher how a point mutation in nmt leads to the development of resistance against an inhibitor series, and enables identification of an NMT inhibitor that can overcome this resistance phenotype.
- Published
- 2019
431. A function of profilin in force generation during malaria parasite motility that is independent of actin binding.
- Author
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Moreau, Catherine A., Quadt, Katharina A., Piirainen, Henni, Kumar, Hirdesh, Bhargav, Saligram P., Strauss, Léanne, Tolia, Niraj H., Wade, Rebecca C., Spatz, Joachim P., Kursula, Inari, and Frischknecht, Friedrich
- Subjects
- *
PLASMODIUM , *MEMBRANE proteins , *MYOSIN , *MICROFILAMENT proteins , *FORCED migration , *OPTICAL tweezers , *SPOROZOITES - Abstract
During transmission of malaria-causing parasites from mosquito to mammal, Plasmodium sporozoites migrate at high speed within the skin to access the bloodstream and infect the liver. This unusual gliding motility is based on retrograde flow of membrane proteins and highly dynamic actin filaments that provide short tracks for a myosin motor. Using laser tweezers and parasite mutants, we previously suggested that actin filaments form macromolecular complexes with plasma membrane-spanning adhesins to generate force during migration. Mutations in the actin-binding region of profilin, a near ubiquitous actin-binding protein, revealed that loss of actin binding also correlates with loss of force production and motility. Here, we show that different mutations in profilin, that do not affect actin binding in vitro, still generate lower force during Plasmodium sporozoite migration. Lower force generation inversely correlates with increased retrograde flow suggesting that, like in mammalian cells, the slow down of flow to generate force is the key underlying principle governing Plasmodium gliding motility. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
432. Flavobacterium johnsoniae Chitinase ChiA Is Required for Chitin Utilization and Is Secreted by the Type IX Secretion System
- Author
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Sampada S. Kharade and Mark J. McBride
- Subjects
Gliding motility ,Chitin ,Biology ,Polysaccharide ,Flavobacterium ,Microbiology ,Gene Expression Regulation, Enzymologic ,chemistry.chemical_compound ,Bacterial Proteins ,Secretion ,Molecular Biology ,Glycoside hydrolase family 18 ,chemistry.chemical_classification ,Chitinases ,Gene Expression Regulation, Bacterial ,Articles ,biology.organism_classification ,Complementation ,chemistry ,Biochemistry ,Mutation ,Chitinase ,biology.protein - Abstract
Flavobacterium johnsoniae, a member of phylum Bacteriodetes, is a gliding bacterium that digests insoluble chitin and many other polysaccharides. A novel protein secretion system, the type IX secretion system (T9SS), is required for gliding motility and for chitin utilization. Five potential chitinases were identified by genome analysis. Fjoh_4555 (ChiA), a 168.9-kDa protein with two glycoside hydrolase family 18 (GH18) domains, was targeted for analysis. Disruption of chiA by insertional mutagenesis resulted in cells that failed to digest chitin, and complementation with wild-type chiA on a plasmid restored chitin utilization. Antiserum raised against recombinant ChiA was used to detect the protein and to characterize its secretion by F. johnsoniae. ChiA was secreted in soluble form by wild-type cells but remained cell associated in strains carrying mutations in any of the T9SS genes, gldK, gldL, gldM, gldNO, sprA, sprE, and sprT. Western blot and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analyses suggested that ChiA was proteolytically processed into two GH18 domain-containing proteins. Proteins secreted by T9SSs typically have conserved carboxy-terminal domains (CTDs) belonging to the TIGRFAM families TIGR04131 and TIGR04183. ChiA does not exhibit strong similarity to these sequences and instead has a novel CTD. Deletion of this CTD resulted in accumulation of ChiA inside cells. Fusion of the ChiA CTD to recombinant mCherry resulted in secretion of mCherry into the medium. The results indicate that ChiA is a soluble extracellular chitinase required for chitin utilization and that it relies on a novel CTD for secretion by the F. johnsoniae T9SS.
- Published
- 2013
433. Deletion of the Cytophaga hutchinsonii type IX secretion system gene sprP results in defects in gliding motility and cellulose utilization
- Author
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Mark J. McBride and Yongtao Zhu
- Subjects
Gliding motility ,Genetic Complementation Test ,Mutant ,Mutagenesis (molecular biology technique) ,Motility ,General Medicine ,Cytophaga ,Biology ,Applied Microbiology and Biotechnology ,Complementation ,Gingipain ,Mutagenesis, Insertional ,Biochemistry ,DNA Transposable Elements ,Secretion ,Transposon mutagenesis ,Cellulose ,Bacterial Secretion Systems ,Gene Deletion ,Locomotion ,Biotechnology - Abstract
Cytophaga hutchinsonii glides rapidly over surfaces and employs a novel collection of cell-associated proteins to digest crystalline cellulose. HimarEm1 transposon mutagenesis was used to isolate a mutant with an insertion in CHU_0170 (sprP) that was partially deficient in gliding motility and was unable to digest filter paper cellulose. SprP is similar in sequence to the Porphyromonas gingivalis type IX secretion system (T9SS) protein PorP that is involved in the secretion of gingipain protease virulence factors and to the Flavobacterium johnsoniae T9SS protein SprF that is needed to deliver components of the gliding motility machinery to the cell surface. We developed an efficient method to construct targeted nonpolar mutations in C. hutchinsonii and deleted sprP. The deletion mutant was defective in gliding and failed to digest cellulose, and complementation with sprP on a plasmid restored both abilities. Sequence analysis predicted that CHU_3105 is secreted by the T9SS, and deletion of sprP resulted in decreased levels of extracellular CHU_3105. The results suggest that SprP may function in protein secretion. The T9SS may be required for motility and cellulose utilization because cell surface proteins predicted to be involved in both processes have C-terminal domains that are thought to target them to this secretion system. The efficient genetic tools now available for C. hutchinsonii should allow a detailed analysis of the cellulolytic, gliding motility, and protein secretion machineries of this common but poorly understood bacterium.
- Published
- 2013
434. The cyanobacterial taxis protein HmpF regulates type IV pilus activity in response to light.
- Author
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Harwood TV, Zuniga EG, Kweon H, and Risser DD
- Subjects
- Gene Expression Regulation, Bacterial radiation effects, Nostoc physiology, Bacterial Proteins genetics, Bacterial Proteins metabolism, Cyanobacteria physiology, Cyanobacteria radiation effects, Fimbriae, Bacterial physiology, Light, Phototaxis
- Abstract
Motility is ubiquitous in prokaryotic organisms including the photosynthetic cyanobacteria where surface motility powered by type 4 pili (T4P) is common and facilitates phototaxis to seek out favorable light environments. In cyanobacteria, chemotaxis-like systems are known to regulate motility and phototaxis. The characterized phototaxis systems rely on methyl-accepting chemotaxis proteins containing bilin-binding GAF domains capable of directly sensing light, and the mechanism by which they regulate the T4P is largely undefined. In this study we demonstrate that cyanobacteria possess a second, GAF-independent, means of sensing light to regulate motility and provide insight into how a chemotaxis-like system regulates the T4P motors. A combination of genetic, cytological, and protein-protein interaction analyses, along with experiments using the proton ionophore carbonyl cyanide m-chlorophenyl hydrazine, indicate that the Hmp chemotaxis-like system of the model filamentous cyanobacterium Nostoc punctiforme is capable of sensing light indirectly, possibly via alterations in proton motive force, and modulates direct interaction between the cyanobacterial taxis protein HmpF, and Hfq, PilT1, and PilT2 to regulate the T4P motors. Given that the Hmp system is widely conserved in cyanobacteria, and the finding from this study that orthologs of HmpF and T4P proteins from the distantly related model unicellular cyanobacterium Synechocystis sp. strain PCC6803 interact in a similar manner to their N. punctiforme counterparts, it is likely that this represents a ubiquitous means of regulating motility in response to light in cyanobacteria., Competing Interests: The authors declare no competing interest.
- Published
- 2021
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435. Actin polymerization mediated by Babesia gibsoni aldolase is required for parasite invasion
- Author
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Makoto Igarashi, Yamagishi Junya, Youn-Kyoung Goo, Dong-Il Chung, Xuenan Xuan, Jungyeon Kim, Yoshifumi Nishikawa, Mohamad Alaa Terkawi, G. Oluga Aboge, Akio Ueno, and Yeonchul Hong
- Subjects
Cytochalasin D ,DNA, Complementary ,Erythrocytes ,Gliding motility ,Immunology ,Protozoan Proteins ,Babesia ,Motility ,macromolecular substances ,Polymerization ,Mice ,Open Reading Frames ,chemistry.chemical_compound ,Fructose-Bisphosphate Aldolase ,parasitic diseases ,Animals ,Parasite hosting ,Actin ,Nucleic Acid Synthesis Inhibitors ,Mice, Inbred ICR ,biology ,Aldolase A ,Toxoplasma gondii ,General Medicine ,DNA, Protozoan ,biology.organism_classification ,Actins ,Cell biology ,Kinetics ,Infectious Diseases ,chemistry ,biology.protein ,Female ,Parasitology - Abstract
Host cell invasion by apicomplexan parasites driven by gliding motility and empowered by actin-based movement is essential for parasite survival and pathogenicity. The parasites share a conserved invasion process: actin-based motility led by the coordination of adhesin-cytoskeleton via aldolase. A number of studies of host cell invasion in the Plasmodium species and Toxoplasma gondii have been performed. However, the mechanisms of host cell invasion by Babesia species have not yet been studied. Here, we show that Babesia gibsoni aldolase (BgALD) forms a complex with B. gibsoni thrombospondin-related anonymous protein (BgTRAP) and B. gibsoni actin (BgACT), depending on tryptophan-734 (W-734) in BgTRAP. In addition, actin polymerization is mediated by BgALD. Moreover, cytochalasin D, which disrupts actin polymerization, suppressed B. gibsoni parasite growth and inhibited the host cell invasion by parasites, indicating that actin dynamics are essential for erythrocyte invasion by B. gibsoni. This study is the first molecular approach to determine the invasion mechanisms of Babesia species.
- Published
- 2013
436. Invasion factors of apicomplexan parasites: essential or redundant?
- Author
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Freddy Frischknecht, Markus Meissner, and David J. P. Ferguson
- Subjects
Microbiology (medical) ,Virulence Factors ,Gliding motility ,Protozoan Proteins ,Myosins ,Biology ,Endocytosis ,Models, Biological ,Microbiology ,Apicomplexa ,03 medical and health sciences ,Myosin ,parasitic diseases ,Cell Adhesion ,Animals ,Humans ,Cell adhesion ,030304 developmental biology ,0303 health sciences ,Gene knockdown ,030306 microbiology ,Ecology ,Intracellular parasite ,biology.organism_classification ,Actin cytoskeleton ,Cell biology ,Actin Cytoskeleton ,Infectious Diseases ,Host-Pathogen Interactions ,Locomotion - Abstract
Apicomplexa are obligate intracellular parasites that cause several human and veterinary diseases worldwide. In contrast to most intracellular pathogens these protozoans are believed to invade a rather passive host cell in a process, that is, tightly linked to the ability of the parasites to move by gliding motility. Indeed specific inhibitors against components of the gliding machinery and the analysis of knockdown mutants demonstrate a linkage of gliding motility and invasion. Intriguingly, new data show that it is possible to block gliding motility, while host cell invasion still occurs. This suggests that either the current models established for host cell invasion need to be critically revised or that alternative, motor independent mechanisms are in place including a more active role of the host cell that can complement a missing actin-myosin-system. Here we discuss some of the discrepancies that need to be addressed for a better understanding of invasion. © 2013.
- Published
- 2013
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437. Alternative conformation of the C-domain of the P140 protein from Mycoplasma genitalium.
- Author
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Vizarraga D, Pérez-Luque R, Martín J, Fita I, and Aparicio D
- Subjects
- Bacterial Proteins genetics, Bacterial Proteins metabolism, Crystallography, X-Ray, Models, Molecular, Molecular Weight, Protein Conformation, Protein Domains, Bacterial Proteins chemistry, Mycoplasma genitalium chemistry
- Abstract
The human pathogen Mycoplasma genitalium is responsible for urethritis in men, and for cervicitis and pelvic inflammatory disease in women. The adherence of M. genitalium to host target epithelial cells is mediated through an adhesion complex called Nap, which is essential for infectivity. Nap is a transmembrane dimer of heterodimers of the immunodominant proteins P110 and P140. The M. genitalium genome contains multiple copies of portions that share homology with the extracellular regions of P140 and P110 encoded by the genes mg191 and mg192, respectively. Homologous recombination between the genes and the copies allows the generation of a large diversity of P140 and P110 variants to overcome surveillance by the host immune system. Interestingly, the C-terminal domain (C-domain) of the extracellular region of P140, which is essential for the function of Nap by acting as a flexible stalk anchoring the protein to the mycoplasma membrane, presents a low degree of sequence variability. In the present work, the X-ray crystal structures of two crystal forms of a construct of the P140 C-domain are reported. In both crystal forms, the construct forms a compact octamer with D4 point-group symmetry. The structure of the C-domain determined in this work presents significant differences with respect to the structure of the C-domain found recently in intact P140. The structural plasticity of the C-domain appears to be a possible mechanism that may help in the functioning of the mycoplasma adhesion complex.
- Published
- 2020
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438. A Continuous Network of Lipid Nanotubes Fabricated from the Gliding Motility of Kinesin Powered Microtubule Filaments
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Amanda Carroll-Portillo, George D. Bachand, Darryl Y. Sasaki, Nathan F. Bouxsein, and Marlene Bachand
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Models, Molecular ,Nanotube ,Materials science ,Protein Conformation ,Surface Properties ,Gliding motility ,Movement ,Kinesins ,Microtubules ,Nanomaterials ,Quantitative Biology::Subcellular Processes ,Phase (matter) ,Electrochemistry ,Molecular motor ,Nanotechnology ,General Materials Science ,Phospholipids ,Spectroscopy ,Mechanical Phenomena ,Physics::Biological Physics ,Nanotubes ,Adhesiveness ,Surfaces and Interfaces ,Condensed Matter Physics ,Quantum dot ,Biophysics ,Kinesin ,Energy source - Abstract
Synthetic interconnected lipid nanotube networks were fabricated on the millimeter scale based on the simple, cooperative interaction between phospholipid vesicles and kinesin-microtubule (MT) transport systems. More specifically, taxol-stabilized MTs, in constant 2D motion via surface absorbed kinesin, extracted and extended lipid nanotube networks from large Lα phase multilamellar liposomes (5-25 μm). Based on the properties of the inverted motility geometry, the total size of these nanofluidic networks was limited by MT surface density, molecular motor energy source (ATP), and total amount and physical properties of lipid source material. Interactions between MTs and extended lipid nanotubes resulted in bifurcation of the nanotubes and ultimately the generation of highly branched networks of fluidically connected nanotubes. The network bifurcation was easily tuned by changing the density of microtubules on the surface to increase or decrease the frequency of branching. The ability of these networks to capture nanomaterials at the membrane surface with high fidelity was subsequently demonstrated using quantum dots as a model system. The diffusive transport of quantum dots was also characterized with respect to using these nanotube networks for mass transport applications.
- Published
- 2013
439. Gliding Motility and Por Secretion System Genes Are Widespread among Members of the Phylum Bacteroidetes
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Mark J. McBride and Yongtao Zhu
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Models, Molecular ,Bacterial gliding ,animal structures ,Virulence Factors ,Gliding motility ,Motility ,Virulence ,Biology ,Models, Biological ,Microbiology ,stomatognathic system ,Bacterial Proteins ,Secretion ,Bacterial Secretion Systems ,Molecular Biology ,Porphyromonas gingivalis ,Bacteroidetes ,musculoskeletal, neural, and ocular physiology ,Articles ,biology.organism_classification ,Gingipain ,human activities ,Genome, Bacterial ,Locomotion - Abstract
The phylum Bacteroidetes is large and diverse, with rapid gliding motility and the ability to digest macromolecules associated with many genera and species. Recently, a novel protein secretion system, the Por secretion system (PorSS), was identified in two members of the phylum, the gliding bacterium Flavobacterium johnsoniae and the nonmotile oral pathogen Porphyromonas gingivalis . The components of the PorSS are not similar in sequence to those of other well-studied bacterial secretion systems. The F. johnsoniae PorSS genes are a subset of the gliding motility genes, suggesting a role for the secretion system in motility. The F. johnsoniae PorSS is needed for assembly of the gliding motility apparatus and for secretion of a chitinase, and the P. gingivalis PorSS is involved in secretion of gingipain protease virulence factors. Comparative analysis of 37 genomes of members of the phylum Bacteroidetes revealed the widespread occurrence of gliding motility genes and PorSS genes. Genes associated with other bacterial protein secretion systems were less common. The results suggest that gliding motility is more common than previously reported. Microscopic observations confirmed that organisms previously described as nonmotile, including Croceibacter atlanticus , “ Gramella forsetii ,” Paludibacter propionicigenes , Riemerella anatipestifer , and Robiginitalea biformata , exhibit gliding motility. Three genes ( gldA , gldF , and gldG ) that encode an apparent ATP-binding cassette transporter required for F. johnsoniae gliding were absent from two related gliding bacteria, suggesting that the transporter may not be central to gliding motility.
- Published
- 2013
440. Characterization of myxobacterial A-motility: insights from microcinematographic observations
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Matthias K. Koch and Egbert Hoiczyk
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biology ,Gliding motility ,ved/biology ,ved/biology.organism_classification_rank.species ,Motility ,General Medicine ,biology.organism_classification ,Cell morphology ,Applied Microbiology and Biotechnology ,Pilus ,Microbiology ,Cell biology ,Cytoskeleton ,Myxococcus xanthus ,Model organism ,Cell rotation - Abstract
Myxococcus xanthus, a predatory soil bacterium, has long been used as a model organism to study bacterial gliding motility. Research has revealed that two fundamentally distinct motor systems power gliding in this bacterium: repeated extensions and retractions of pili mediate social or (S-) motility, whereas the motor powering adventurous or (A-) motility has not yet been identified with certainty. Several different hypotheses to explain A-motility have been suggested and differ with respect to the involved motor structures as well as the mechanics of motility. As some of the more recent models invoke helically arranged structures and processes that require rotations of the cell, we decided to re-examine myxobacterial motility using microcinematographic techniques. This re-examination was also prompted by the lack of direct experimental data on the rotation of M. xanthus during gliding. Microcinematographic observations of deformed cells and cells containing large stationary intracellular structures reveal clearly that M. xanthus gliding does not require cell rotation.
- Published
- 2013
441. Symbiosis between the cyanobacterium Nostoc and the liverwort Blasia requires a CheR-type MCP methyltransferase
- Author
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Paula S. Duggan, Teresa Thiel, and David G. Adams
- Subjects
Cyanobacteria ,Nostoc ,biology ,Symbiosis ,Interaction with host ,Gliding motility ,Botany ,General Agricultural and Biological Sciences ,Blasia ,biology.organism_classification ,Hormogonium ,Gene ,Cell biology - Abstract
In response to environmental change, the cyanobacterium Nostoc punctiforme ATCC 29133 produces highly adapted filaments known as hormogonia that have gliding motility and serve as the agents of infection in symbioses with plants. Hormogonia sense and respond to unidentified plant-derived chemical signals that attract and guide them towards the symbiotic tissues of the host. There is increasing evidence to suggest that their interaction with host plants is regulated by chemotaxis-related signal transduction systems. The genome of N. punctiforme contains multiple sets of chemotaxis (che)-like genes. In this study we characterize the large che5 locus of N. punctiforme. Disruption of NpR0248, which encodes a putative CheR methyltransferase, results in loss of motility and significantly impairs symbiotic competency with the liverwort Blasia pusilla when compared with the parent strain. Our results suggest that chemotaxis-like elements regulate hormogonia function and hence symbiotic competency in this system.
- Published
- 2012
442. Shape change in the receptor for gliding motility in Plasmodium sporozoites
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Adem C. Koksal, Timothy A. Springer, Chafen Lu, and Gaojie Song
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Models, Molecular ,Plasmodium ,Gliding motility ,Movement ,Molecular Sequence Data ,Static Electricity ,Integrin ,Protozoan Proteins ,Motility ,Receptors, Cell Surface ,Models, Biological ,Protein Structure, Secondary ,Animals ,Amino Acid Sequence ,Peptide sequence ,Actin ,Thrombospondin ,Multidisciplinary ,biology ,fungi ,Biological Sciences ,Transmembrane protein ,Protein Structure, Tertiary ,Cell biology ,Crystallography ,Sporozoites ,Cytoplasm ,biology.protein - Abstract
Sporozoite gliding motility and invasion of mosquito and vertebrate host cells in malaria is mediated by thrombospondin repeat anonymous protein (TRAP). Tandem von Willebrand factor A (VWA) and thrombospondin type I repeat (TSR) domains in TRAP connect through proline-rich stalk, transmembrane, and cytoplasmic domains to the parasite actin-dependent motility apparatus. We crystallized fragments containing the VWA and TSR domains from Plasmodium vivax and Plasmodium falciparum in different crystal lattices. TRAP VWA domains adopt closed and open conformations, and bind a Mg 2+ ion at a metal ion–dependent adhesion site implicated in ligand binding. Metal ion coordination in the open state is identical to that seen in the open high-affinity state of integrin I domains. The closed VWA conformation associates with a disordered TSR domain. In contrast, the open VWA conformation crystallizes with an extensible β ribbon and ordered TSR domain. The extensible β ribbon is composed of disulfide-bonded segments N- and C-terminal to the VWA domain that are largely drawn out of the closed VWA domain in a 15 Å movement to the open conformation. The extensible β ribbon and TSR domain overlap at a conserved interface. The VWA, extensible β ribbon, and TSR domains adopt a highly elongated overall orientation that would be stabilized by tensile force exerted across a ligand-receptor complex by the actin motility apparatus of the sporozoite. Our results provide insights into regulation of “stick-and-slip” parasite motility and for development of sporozoite subunit vaccines.
- Published
- 2012
443. Chemosensory signaling controls motility and subcellular polarity in Myxococcus xanthus
- Author
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David R. Zusman, Christine Kaimer, and James E. Berleman
- Subjects
Microbiology (medical) ,Myxococcus xanthus ,biology ,Gliding motility ,Chemotaxis ,Cell Polarity ,Motility ,biology.organism_classification ,Microbiology ,Protein subcellular localization prediction ,Article ,Pilus ,Cell biology ,Transport protein ,Protein Transport ,Infectious Diseases ,Bacterial Proteins ,Cell polarity ,Locomotion ,Signal Transduction - Abstract
Myxococcus xanthus is a model system for the study of dynamic protein localization and cell polarity in bacteria. M. xanthus cells are motile on solid surfaces enabled by two forms of gliding motility. Motility is controlled by the Che-like Frz pathway, which is essential for fruiting body formation and differentiation. The Frz signal is mediated by a GTPase/GAP protein pair that establishes cell polarity and directs the motility systems. Pilus driven motility at the leading pole of the cell requires dynamic localization of two ATPases and the coordinated production of EPS synthesis. Gliding motility requires dynamic movement of large protein complexes, but the mechanism by which this system generates propulsive force is still an active area of investigation.
- Published
- 2012
444. Use of a Mariner-Based Transposon Mutagenesis System To Isolate Clostridium perfringens Mutants Deficient in Gliding Motility
- Author
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Abraham L. Sonenshein, Hualan Liu, Stephen B. Melville, and Laurent Bouillaut
- Subjects
Transposable element ,Clostridium perfringens ,Gliding motility ,Movement ,Mutant ,Transposases ,Mutagenesis (molecular biology technique) ,Biology ,medicine.disease_cause ,Microbiology ,Gene Expression Regulation, Enzymologic ,Pilus ,Bacterial Proteins ,medicine ,Molecular Biology ,Transposase ,Genetics ,Genetic Complementation Test ,Chromosome Mapping ,Articles ,Gene Expression Regulation, Bacterial ,Chromosomes, Bacterial ,DNA-Binding Proteins ,RNA, Bacterial ,Mutagenesis ,RNA, Ribosomal ,Mutation ,DNA Transposable Elements ,Transposon mutagenesis ,Plasmids - Abstract
Clostridium perfringens is an anaerobic Gram-positive pathogen that causes many human and animal diseases, including food poisoning and gas gangrene. C. perfringens lacks flagella but possesses type IV pili (TFP). We have previously shown that C. perfringens can glide across an agar surface in long filaments composed of individual bacteria attached end to end and that two TFP-associated proteins, PilT and PilC, are needed for this. To discover additional gene products that play a role in gliding, we developed a plasmid-based mariner transposon mutagenesis system that works effectively in C. perfringens. More than 10,000 clones were screened for mutants that lacked the ability to move away from the edge of a colony. Twenty-four mutants (0.24%) were identified that fit the criteria. The genes containing insertions that affected gliding motility fell into nine different categories. One gene, CPE0278, which encodes a homolog of the SagA cell wall-dependent endopeptidase, acquired distinct transposon insertions in two independent mutants. sagA mutants were unable to form filaments due to a complete lack of end-to-end connections essential for gliding motility. Complementation of the sagA mutants with a wild-type copy of the gene restored gliding motility. We constructed an in-frame deletion mutation in the sagA gene and found that this mutant had a phenotype similar to those of the transposon mutants. We hypothesize that the sagA mutant strains are unable to form the molecular complexes which are needed to keep the cells in an end-to-end orientation, leading to separation of daughter cells and the inability to carry out gliding motility.
- Published
- 2012
445. Analysis of energy sources forMycoplasma penetransgliding motility
- Author
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Mitchell F. Balish, Michael R. Hughes, and Dominika A. Jurkovic
- Subjects
Hot Temperature ,animal structures ,Gliding motility ,Phase contrast microscopy ,Motility ,Biology ,Bacterial Physiological Phenomena ,Positive correlation ,Time-Lapse Imaging ,Microbiology ,Article ,law.invention ,stomatognathic system ,law ,Mycoplasma penetrans ,parasitic diseases ,Genetics ,Humans ,Microscopy, Phase-Contrast ,Molecular Biology ,Chemiosmosis ,musculoskeletal, neural, and ocular physiology ,Temperature ,Hydrogen-Ion Concentration ,biology.organism_classification ,Cell biology ,Microscopy, Fluorescence ,Molecular mechanism ,Energy Metabolism ,Energy source ,human activities - Abstract
Mycoplasma penetrans, a potential human pathogen found mainly in HIV-infected individuals, uses a tip structure for both adherence and gliding motility. To improve our understanding of the molecular mechanism of M. penetrans gliding motility, we used chemical inhibitors of energy sources associated with motility of other organisms to determine which of these is used by M. penetrans and also tested whether gliding speed responded to temperature and pH. Mycoplasma penetrans gliding motility was not eliminated in the presence of a proton motive force inhibitor, a sodium motive force inhibitor, or an agent that depletes cellular ATP. At near-neutral pH, gliding speed increased as temperature increased. The absence of a clear chemical energy source for gliding motility and a positive correlation between speed and temperature suggest that energy derived from heat provides the major source of power for the gliding motor of M. penetrans.
- Published
- 2012
446. Plasmodium berghei plasmepsin VIII is essential for sporozoite gliding motility
- Author
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Babu S. Mastan, Sandeep Dey, Satish Mishra, Kota Arun Kumar, and Sunil Kumar Narwal
- Subjects
0301 basic medicine ,Gliding motility ,Plasmodium berghei ,Movement ,Plasmepsin ,Protozoan Proteins ,Biology ,Salivary Glands ,03 medical and health sciences ,Mice ,Aspartate protease ,parasitic diseases ,Anopheles ,medicine ,Parasite hosting ,Animals ,Aspartic Acid Endopeptidases ,Humans ,Mice, Inbred BALB C ,Oocysts ,Hep G2 Cells ,Gene deletion ,medicine.disease ,biology.organism_classification ,Virology ,Cell biology ,Malaria ,Disease Models, Animal ,030104 developmental biology ,Infectious Diseases ,Culicidae ,Phenotype ,Parasitology ,Sporozoites ,Female - Abstract
Plasmodium aspartic proteases, termed plasmepsins (PMs) play many critical roles such as haemoglobin degradation, cleavage of PEXEL proteins and sporozoite development in the parasite life cycle. Most of the plasmepsins are well characterized, however the role of PM VIII in Plasmodium remains unknown. Here, we elucidate the functions of PM VIII (PBANKA_132910) in the rodent malaria parasite Plasmodium berghei (Pb). By targeted gene deletion, we show that PbPM VIII is critical for sporozoite egress from an oocyst and gliding motility, which is a prerequisite for the invasion of salivary glands and subsequent transmission to the vertebrate host.
- Published
- 2016
447. Working stroke of the kinesin-14, ncd, comprises two substeps of different direction
- Author
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Lukasz Hajdo, Andrzej A. Kasprzak, Elzbieta Dudek, Andrej Vilfan, Stefan Diez, and Bert Nitzsche
- Subjects
0301 basic medicine ,Materials science ,Rotation ,Gliding motility ,Recombinant Fusion Proteins ,Genetic Vectors ,Gene Expression ,Kinesins ,Nanotechnology ,macromolecular substances ,Microtubules ,Motor protein ,03 medical and health sciences ,Adenosine Triphosphate ,0302 clinical medicine ,Microtubule ,Escherichia coli ,Humans ,Stroke (engine) ,Cloning, Molecular ,Oncogene Proteins ,Multidisciplinary ,Fluorescence interference contrast microscopy ,Biomechanical Phenomena ,Longitudinal direction ,Adenosine Diphosphate ,Kinetics ,030104 developmental biology ,Models, Chemical ,PNAS Plus ,Biophysics ,Kinesin ,Biological Assay ,030217 neurology & neurosurgery ,Protein Binding - Abstract
Single-molecule experiments have been used with great success to explore the mechanochemical cycles of processive motor proteins such as kinesin-1, but it has proven difficult to apply these approaches to nonprocessive motors. Therefore, the mechanochemical cycle of kinesin-14 (ncd) is still under debate. Here, we use the readout from the collective activity of multiple motors to derive information about the mechanochemical cycle of individual ncd motors. In gliding motility assays we performed 3D imaging based on fluorescence interference contrast microscopy combined with nanometer tracking to simultaneously study the translation and rotation of microtubules. Microtubules gliding on ncd-coated surfaces rotated around their longitudinal axes in an [ATP]- and [ADP]-dependent manner. Combined with a simple mechanical model, these observations suggest that the working stroke of ncd consists of an initial small movement of its stalk in a lateral direction when ADP is released and a second, main component of the working stroke, in a longitudinal direction upon ATP binding.
- Published
- 2016
448. Filimonas aurantiibacter sp. Nov., an orange pigmented bacterium isolated from lake water and emended description of the genus Filimonas
- Author
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Ramon Rosselló-Móra, Nancy E. Waas, Natalie Cleeve, Jamie L. Pearson, Nikklas Tewalt, Jon Roecker, Shawn C. Pavlons, Hans-Jürgen Busse, and Richard A. Albert
- Subjects
0301 basic medicine ,DNA, Bacterial ,Michigan ,Sequence analysis ,Gliding motility ,Spermidine ,030106 microbiology ,Orange (colour) ,Biology ,Microbiology ,03 medical and health sciences ,Pigment ,Phylogenetics ,RNA, Ribosomal, 16S ,Botany ,Ecology, Evolution, Behavior and Systematics ,Phylogeny ,Base Composition ,Bacteroidetes ,Pigmentation ,Phosphatidylethanolamines ,Fatty Acids ,Flexirubin ,Vitamin K 2 ,General Medicine ,Sequence Analysis, DNA ,Ribosomal RNA ,16S ribosomal RNA ,biology.organism_classification ,Aurantiibacter ,Bacterial Typing Techniques ,Lakes ,030104 developmental biology ,visual_art ,visual_art.visual_art_medium ,Orange pigmented ,Bacteria - Abstract
A Gram-stain-negative bacterium was isolated from Lake Michigan water. 16S rRNA gene sequence analysis revealed that strain 1458 had a sequence similarity to Filimonas lacunae YT21, Sediminibacterium goheungense HME7863, Parasegetibacter terrae SGM2-10, Sediminibacterium ginsengisoli DCY13, Terrimonas ferruginea DSM 30193, Lacibacter cauensis NJ-8, Flavihumibacter solisilvae 3-3, Parasegetibacter luojieneis RHYL-37, Vibrionimonas magnilacihabitans MU-2 and Parafilimonas terrae 5GHs7-2 with values of 93.4, 92.3, 91.9, 91.9, 91.8, 91.6, 91.6, 91.6, 91.5 and 90.4%, respectively. The primary cellular fatty acids were iso-C, iso-C 3-OH, iso-CG and summed feature 3 (iso-C 2-OH/ Cω7c). The primary polar lipids were phosphatidylethanolamine and an unidentified polar lipid only detectable after total polar lipid staining. The quinone system was menaquinone MK-7, and in the polyamine pattern, sym-homospermidine was predominant. Additional phenotypic characteristics included growth at 15 to 40 °C and pH 5.0 to 8.0, a salt tolerance range of 0 to 2.0% (w/v), production of orange cell-bound pigment flexirubin, and gliding motility. After phenotypic, chemotaxonomic and molecular analyses, strain 1458 was identified as a novel species of the genus Filimonas, for which the name Filimonas aurantiibacter sp. nov. is proposed. The type strain is 1458 (=NRRL B-65305=LMG 29039). An emended description of the genus Filimonas is also provided.
- Published
- 2016
449. Interaction of gliding motion of bacteria with rheological properties of the slime
- Author
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Muhammad Sajid, Zeeshan Asghar, and Naeem Ali
- Subjects
0301 basic medicine ,Statistics and Probability ,Bacterial gliding ,Gliding motility ,Differential equation ,Movement ,Constitutive equation ,Perturbation (astronomy) ,Biology ,01 natural sciences ,General Biochemistry, Genetics and Molecular Biology ,Quantitative Biology::Cell Behavior ,010305 fluids & plasmas ,Quantitative Biology::Subcellular Processes ,03 medical and health sciences ,0103 physical sciences ,General Immunology and Microbiology ,Bacteria ,Ecology ,Applied Mathematics ,Glider ,Fluid mechanics ,General Medicine ,Mechanics ,Nonlinear system ,030104 developmental biology ,Modeling and Simulation ,General Agricultural and Biological Sciences ,Rheology ,Locomotion - Abstract
Bacteria which do not have organelles of motility, such as flagella, adopt gliding as a mode of locomotion. In gliding motility bacterium moves under its own power by secreting a layer of slime on the substrate. The exact mechanism by which a glider achieves motility is yet in controversy but there are evidences which support the wave-like undulation on the surface of the organism, as a possible mechanism of motility. Based on this observation, a model of undulating sheet over a layer of slime is examined as a possible model of the gliding motion of a bacterium. Three different non-Newtonian constitutive equations namely, finite extendable nonlinear elastic-peterline (FENE-P), Simplified Phan-Thien-Tanner (SPTT) and Rabinowitsch equations are used to capture the rheological properties of the slime. It is found that the governing equation describing the fluid mechanics of the model under lubrication approximation is same for all the considered three constitutive equations. In fact, it involves a single non-Newtonian parameter which assumes different values for each of the considered constitutive relations. This differential equation is solved using both perturbation and semi-analytic procedure. The perturbation solution is exploited to get an estimate of the speed of the glider for different values of the non-Newtonian parameter. The solution obtained via semi-analytic procedure is used to investigate the important features of the flow field in the layer of the slime beneath the glider when the glider is held fixed. The expression of forces generated by the organism and power required for propulsion are also derived based on the perturbation analysis.
- Published
- 2016
450. Structural Study of MPN387, an Essential Protein for Gliding Motility of a Human-Pathogenic Bacterium, Mycoplasma pneumoniae
- Author
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Keiichi Namba, Yuhei O Tahara, Yoshito Kawakita, Miki Kinoshita, Eisaku Katayama, Isil Tulum, Makoto Miyata, and Yukio Furukawa
- Subjects
0301 basic medicine ,Yellow fluorescent protein ,Mycoplasma pneumoniae ,Gliding motility ,Protein Conformation ,Movement ,030106 microbiology ,Flagellum ,medicine.disease_cause ,Microbiology ,03 medical and health sciences ,Protein structure ,Bacterial Proteins ,medicine ,Amino Acid Sequence ,Molecular Biology ,Peptide sequence ,biology ,Mycoplasma ,Articles ,Gene Expression Regulation, Bacterial ,Cell biology ,Attachment organelle ,biology.protein - Abstract
Mycoplasma pneumoniae is a human pathogen that glides on host cell surfaces with repeated catch and release of sialylated oligosaccharides. At a pole, this organism forms a protrusion called the attachment organelle, which is composed of surface structures, including P1 adhesin and the internal core structure. The core structure can be divided into three parts, the terminal button, paired plates, and bowl complex, aligned in that order from the front end of the protrusion. To elucidate the gliding mechanism, we focused on MPN387, a component protein of the bowl complex which is essential for gliding but dispensable for cytadherence. The predicted amino acid sequence showed that the protein features a coiled-coil region spanning residue 72 to residue 290 of the total of 358 amino acids in the protein. Recombinant MPN387 proteins were isolated with and without an enhanced yellow fluorescent protein (EYFP) fusion tag and analyzed by gel filtration chromatography, circular dichroism spectroscopy, analytical ultracentrifugation, partial proteolysis, and rotary-shadowing electron microscopy. The results showed that MPN387 is a dumbbell-shaped homodimer that is about 42.7 nm in length and 9.1 nm in diameter and includes a 24.5-nm-long central parallel coiled-coil part. The molecular image was superimposed onto the electron micrograph based on the localizing position mapped by fluorescent protein tagging. A proposed role of this protein in the gliding mechanism is discussed. IMPORTANCE Human mycoplasma pneumonia is caused by a pathogenic bacterium, Mycoplasma pneumoniae . This tiny, 2-μm-long bacterium is suggested to infect humans by gliding on the surface of the trachea through binding to sialylated oligosaccharides. The mechanism underlying mycoplasma “gliding motility” is not related to any other well-studied motility systems, such as bacterial flagella and eukaryotic motor proteins. Here, we isolated and analyzed the structure of a key protein which is directly involved in the gliding mechanism.
- Published
- 2016
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