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Summary: Ultrastructural observations of the wood-inhabiting fungal- and plant-feeding nematode, Bursaphelenchus mucronatus , revealed intracellular bacteria in the male and female gonads. In males, bacteria were present inside the testis epithelial cells, spermatocytes, spermatids and immature spermatozoa. Spermatheca of females contained amoeboid pseudopod-bearing mature spermatozoa with bacteria closely associated with the sperm nucleus. Tissues of the females studied were free from bacteria. The gram-negative bacteria in their localisation, size, ultrastructure, and especially characteristic internal bundle of parallel filaments, were identified preliminary as related to the genus Cardinium (Bacteroidetes), which includes obligate endosymbionts of diverse arthropods and is known to be associated with several species of plant-parasitic nematodes. [ABSTRACT FROM AUTHOR]

Introduction Actinomycosis is an unusual chronic granulomatous infectious disease. They are commensals in various sites of the human body but with little pathogenicity. Actinomyces israelii is the most prevalent species but more than 30 species have been described. Infection of the lower respiratory tract is unusual, the involvement of mediastinum being even rarer. Case report A 63-year-old man, previously healthy and living in a rural area, presented with a 5-month history of hemoptysis, pleuritic pain, weight loss, and night sweats. Community-acquired pneumonia with a mediastinal mass was documented, for which he received antibiotic management. Thoracoscopy was carried out for diagnosis and resection of the mediastinal mass due to inconclusive findings in the percutaneous biopsy. Pathology reported the presence of filamentous Gram-positive bacteria visible in Grocott staining. Due to the pathology findings, and the fact that no other infectious agents were identified, a diagnosis of actinomycosis was established. Treatment with oral amoxicillin 1g TID for 6 months was initiated. Conclusions As far as we are aware, we present the sixth case of mediastinal actinomycosis. We present this case to bring attention to this rare but clinically relevant presentation to be considered as a differential diagnosis of mediastinal masses and to emphasize the need for specific anaerobic cultures to improve the diagnostic yield. [ABSTRACT FROM AUTHOR]

Concurrent Clostridium piliforme and canine distemper virus (CDV) infection was diagnosed in 2 canine littermates and 1 gray fox kit from Texas, USA. In all 3 animals, intracytoplasmic, filamentous bacteria, consistent with C. piliforme, were present along the margins of foci of hepatic necrosis. Additional histologic findings included intracytoplasmic and intranuclear inclusion bodies in bile duct and bronchial epithelial cells of the fox kit, and mild intestinal necrosis in 1 puppy. PCR assays confirmed the presence of C. piliforme in all 3 animals, CDV in both puppies, and canine parvovirus in 1 puppy. Fluorescent antibody testing confirmed the presence of CDV in the fox kit. Concurrent canine distemper and Tyzzer disease in canine littermates and the gray fox has not been reported previously, to our knowledge. [ABSTRACT FROM AUTHOR]

The relationship between a quality of activated sludge microbiota and wastewater treatment plant (WWTP) operational stability has been defined in the past few decades. However, this dependence is not so clear in the case of industrial wastewater treatment. In this article, a very specific example of industrial textile wastewater treatment plant (ITWTP) is analyzed. Textile effluents are well known as highly contaminated wastewater containing many biodegradable compounds. Microscopic analysis included flocs morphology examination, attempts to evaluate the Sludge Biotic Index (SBI), and identification of dominant filamentous microorganisms. Routine operational control of ITWTP covered pH, temperature, redox potential, dissolved oxygen and COD measurements. The average ecosystem existing in the described ITWTP differed significantly compared to municipal WWTPs. The flocs were smaller and irregular. Filamentous bacteria did not cause foaming although filaments index reached 4. Nostocoida limicola I dominated with significant amounts of type 0041 and type 021N. The evaluation of SBI was impossible as the most of protozoan was in the form of cysts. The overall microbiota diversity correlated with COD removal in activated sludge unit of ITWTP. [ABSTRACT FROM AUTHOR]

CRISPR/Cas technology is a versatile tool for genome engineering in many organisms, including filamentous fungi. Cpf1 is a multi-domain protein of class 2 (type V) RNA-guided CRISPR/Cas endonuclease, and is an alternative platform with distinct features when compared to Cas9. However, application of this technology in filamentous fungi is limited. Here, we present a single CRISPR/Cpf1 plasmid system in Aspergillus aculeatus strain TBRC 277, an industrially relevant cell factory. We first evaluated the functionality of three Cpf1 orthologs from Acidaminococcus sp. BV3L6 (AsCpf1), Francisella tularensis subsp. novicida U112 (FnCpf1), and Lachnospiraceae bacterium (LbCpf1), in RNA-guided site-specific DNA cleavage at the pksP locus. FnCpf1 showed the highest editing efficiency (93 %) among the three Cpf1s. It was further investigated for its ability to delete a 1.7 kb and a 0.5 kb from pksP and pyr G genes, respectively, using two protospacers targeting these gene loci in a single crRNA array. Lastly, simultaneous editing of three sites within TBRC 277 genome was performed using three guide sequences targeting these two genes as well as an additional gene, kusA , which resulted in combined editing efficiency of 40 %. The editing of the NHEJ pathway by targeting kusA to generate a NHEJ-deficient strain of A. aculeatus TBRC 277 improved gene targeting efficiency and yielded more precise gene-editing than that of using wild-type strain. This promising genome-editing system can be used for strain improvement in industrial applications such as production of valuable bioproducts. [ABSTRACT FROM AUTHOR]

The possibility of the developing a biochemical oxygen demand (BOD) biosensor based on electroactive biofilms of activated sludge grown on the surface of a graphite-paste electrode modified with carbon nanotubes was studied. A complex of microscopic methods controlled biofilm formation: optical microscopy with phase contrast, scanning electron microscopy, and laser confocal microscopy. The features of charge transfer in the obtained electroactive biofilms were studied using the methods of cyclic voltammetry and electrochemical impedance spectroscopy. The rate constant of the interaction of microorganisms with the extracellular electron carrier (0.79 ± 0.03 dm3(g s)−1) and the heterogeneous rate constant of electron transfer (0.34 ± 0.02 cm s−1) were determined using the cyclic voltammetry method. These results revealed that the modification of the carbon nanotubes' (CNT) electrode surface makes it possible to create electroactive biofilms. An analysis of the metrological and analytical characteristics of the created biosensors showed that the lower limit of the biosensor based on an electroactive biofilm of activated sludge is 0.41 mgO2/dm3, which makes it possible to analyze almost any water sample. Analysis of 12 surface water samples showed a high correlation (R2 = 0.99) with the results of the standard method for determining biochemical oxygen demand. [ABSTRACT FROM AUTHOR]

The Anabaena genus is a model organism of filamentous cyanobacteria whose vegetative cells can differentiate under nitrogen-limited conditions into a type of cell called heterocyst. These heterocysts lose the possibility to divide and are necessary for the colony because they can fix and share environmental nitrogen. In order to distribute the nitrogen efficiently, heterocysts are arranged to form a quasi-regular pattern whose features are maintained as the filament grows. Recent efforts have allowed advances in the understanding of the interactions and genetic mechanisms underlying this dynamic pattern. However, the main role of the patA and hetF genes are yet to be clarified; in particular, the patA mutant forms heterocysts almost exclusively in the terminal cells of the filament. In this work, we investigate the function of these genes and provide a theoretical model that explains how they interact within the broader genetic network, reproducing their knock-out phenotypes in several genetic backgrounds, including a nearly uniform concentration of HetR along the filament for the patA mutant. Our results suggest a role of hetF and patA in a post-transcriptional modification of HetR which is essential for its regulatory function. In addition, the existence of molecular leakage out of the filament in its boundary cells is enough to explain the preferential appearance of terminal heterocysts, without any need for a distinct regulatory pathway. Author summary: Understanding multicellular pattern formation is key for the study of both natural and synthetic developmental processes. Arguably one of the simplest model systems for this is the filamentous cyanobacterium Anabaena, that in conditions of nitrogen deprivation undergoes a dynamical differentiation process that differentiates roughly one in every ten cells into nitrogen-fixing heterocysts, in a quasi-regular pattern that is maintained as the filament keeps growing. One of the most characteristic mutations affecting this process forms heterocysts mostly constrained to the terminal cells of the filament. We have used experimental observations to propose a mathematical model of heterocyst differentiation able to reproduce this striking phenotype. The model extends our understanding of the regulations in this pattern-forming system and makes several predictions on molecular interactions. Importantly, a key aspect is the boundary condition at the filament's ends: inhibitors of differentiation should be able to leak out of the filament, or otherwise the terminal cells would not differentiate. This highlights, in a very clear example, the importance of considering physical constraints in developmental processes. [ABSTRACT FROM AUTHOR]

Lipases are enzymes that hydrolyze triglycerides to fatty acids and glycerol. A typical element in lipases is a conserved motif of five amino acids (the pentapeptide), most commonly G-X-S-X-G. Lipases with the pentapeptide A-X-S-X-G are present in species of Bacillus, Paucimonas lemoignei, and the yeast Trichosporon asahii; they are usually thermotolerant and solvent resistant. Recently, while searching for true lipases in the Trichoderma harzianum genome, one lipase containing the pentapeptide AHSMG was identified. In this study, we cloned from T. harzianum strain B13-1 the lipase ID135964, renamed here as ThaL, which is 97.65% identical with the reference. We found that ThaL is a lid-containing true lipase of cluster III that belongs to a large family comprising highly conserved proteins in filamentous fungi in the orders Hypocreales and Glomerellales, in which predominantly pathogenic fungi are found. ThaL was expressed in conidia, as well as in T. harzianum mycelium, where it was cultured in liquid minimal medium. These results—together with the amino acid composition, absence of a signal peptide, mitochondrial sorting prediction, disordered regions in the protein, and lineage-specific phylogenetic distribution of its homologs—suggest that ThaL is a non-canonical effector. In summary, AHSMG-lipase is a novel lipase family in filamentous fungi, and is probably involved in pathogenicity. [ABSTRACT FROM AUTHOR]

Antimicrobial peptides (AMPs) play important roles in host innate immune systems. Anti-lipopolysaccharide factor (ALF), which is a primary AMP in crustaceans, is active against bacteria, fungi and some viruses. MjALF-D, an anionic peptide, is a group D ALF isolated from Marsupenaeus japonicus. In the present study, a series of experiments were performed to study its antibacterial spectrum and further explore its antibacterial and bacterial binding activities. Liquid growth inhibition data demonstrated that recombinant MjALF-D (rMjALF-D) possessed strong antibacterial activity against the gram-positive bacterium Micrococcus luteus and the gram-negative bacterium Photobacterium damselae , with a minimum inhibitory concentration (MIC) or minimum bactericidal concentration (MBC) lower than 1.25 μM. The kinetic analysis showed that the antibacterial activity of rMjALF-D was dose- and time-dependent. Additionally, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations the potential bactericidal process. rMjALF-D treatment resulted in a large number of unidentified filamentous structures wrapped around the bacteria, and during the incubation, the cell surface became obviously rough and disrupted. rMjALF-D showed distinct binding ability after direct incubation with M. luteus and P. damselae but no binding ability to Escherichia coli , which was weakly inhibited by rMjALF-D. These data suggest that MjALF-D displays modest antibacterial activity and may provide more insights into the function and role of ALF in shrimp immunity. • Based on the detection of its antibacterial spectrum, rMjALF-D exerted modest bactericidal activity. • The bactericidal activity of rMjALF-D against bacteria is dependent on both the dose and time. • rMjALF-D could induce leakage of the cytoplasmic content of the bacteria. • rMjALF-D binds to Micrococcus luteus and Photobacterium damselae but not to Escherichia coli. • rMjALF-D played multiple roles in the bactericidal process. [ABSTRACT FROM AUTHOR]

Aims: This study aimed to unveil perrhenate sorption properties of the filamentous sheaths formed by Sphaerotilus montanus, Sphaerotilus natans and Thiothrix fructosivorans. Methods and Results: The adsorptions of perrhenate on lyophilizates of the above‐mentioned filamentous sheaths were analysed by ICP, IR, XPS and EDX. The capacity reached 82 mg per g‐adsorbent, when using S. natans. The Langmuir coefficient of this adsorbent was found to be the largest of the three. The adsorption capacity was discussed with respect to the amount of nitrogen and phosphorus in the adsorbents. The occurrence of anion exchange was implied by the IR spectrum changes before and after adsorption. The adsorption data fitted well with a pseudo‐second‐order equation, suggesting that the rate is determined by the chemical bond formation. Conclusions: A significant amount of perrhenate was adsorbed on the sheaths formed by S. montanus, S. natans and T. fructosivorans. The adsorption was correlated with the elemental compositions. A strong chemical bond formation was suggested from the results of the Langmuir adsorption isotherm and kinetic analysis. Significance and Impact of Study: The capacity obtained for S. natans is one of the largest adsorptions amongst the similar biomaterials, implying the possibility of providing economical adsorbents of rare metal oxyanions. [ABSTRACT FROM AUTHOR]

During a study of biodiversity of cyanobacteria in Gorely volcano soils (Kamchatka Peninsula), a strain of heterocytous, a false branching cyanobacterium with gradually tapered filaments, was isolated. Prominent features of the strain were purplish-grey trichomes and firm, distinct multilayered sheaths. Based on the results obtained from the morphological, ecological, and phylogenetic analysis using the 16S rRNA and 16S–23S ITS region, 16S–23S ITS secondary structure analysis, comparison of flanking regions of BoxB and V3 helices, and the p-distance between the 16S–23S ITS region, we describe our strain K7 as a novel species of the genus Roholtiella with the name Roholtiella volcanica sp. nov., in accordance with the International Code of Nomenclature for algae, fungi, and plants. This work continues the rapid expansion of the description of new taxa of cyanobacteria, and particularly demonstrates a coming phase in cyanobacterial taxonomy in which the discovery of new species in recently described genera rapidly increases our understanding of the diversity in this phylum. [ABSTRACT FROM AUTHOR]

The present study is aimed at isolating a heavy metal and non-metallic pollutants tolerant microorganism from wastewater samples which has the highest capability to remove toxicants from contaminated water bodies. From the wastewater samples of Tolly Canal, 35 bacterial, 10 yeast and 5 filamentous fungal strains were isolated and tested for their toxicant tolerance capacities. The obtained isolates were subjected to gradually increasing concentration of toxic metal salts Pb(CH3COO)2.3H2O, NiSO4.6H2O, CuSO4.5H2O, CdCl2.H2O, NaF, NaAsO2. All the isolated strains reached the minimal inhibitory concentration much earlier than a yeast strain named as JIC. The strain was proved to be the most toxicant tolerant and also showed efficient toxicant removal capacity by employing 10 ppm of each of the pollutants. It showed removal capacities of Cd (II) (43.60%), Pb (II) (38.20%), Cu (II) (22.60%), As (III) (31.20%), F−(27.60%) and Ni (II) (24.80%). The isolated strain has been undergone some biochemical and phylogenetic analyses for identification and subsequently found to be a strain of Candida tropicalis. The Internal Transcribed Spacer (ITS) 1–4 RNA gene sequence obtained was deposited to National Center for Biotechnology Information (NCBI) and finally the accession number has been obtained as Candida tropicalis isolate JIC MZ798901. [ABSTRACT FROM AUTHOR]

The interest in the ability of phages to control bacterial populations has extended from medical applications into the fields of agriculture, aquaculture, and the food industry. In particular, several authors have proposed using bacteriophages as an alternative method to control foaming and bulking in wastewater treatment. This strategy has shown successful results at the laboratory scale. However, this technology is still in development, and there are several challenges to overcome before bacteriophages can be widely used to control foaming and bulking in pilot or larger-scale treatment plants. Several models of the infection mechanisms in individual bacteria–phage pairs have been reported, i.e., for controlled systems with only one bacterium species in the presence of one phage species. However, activated sludge treatment systems largely differ from this situation, which opens a large horizon for future research. Mathematical models will play a key role in this development process, and this review offers an overview of the proposed models: their applications, potential, and challenges. A particular focus is placed on the model properties, such as parameter identifiability and states' observability, which are essential for process prediction, monitoring, or dynamic optimization. [ABSTRACT FROM AUTHOR]

Background: Filamentous fungi are highly efficient at deconstructing plant biomass by secreting a variety of enzymes, but the complex enzymatic regulation underlying this process is not conserved and remains unclear. Results: In this study, cellulases and xylanases could specifically respond to Avicel- and xylan-induction, respectively, in lignocellulose-degrading strain Trichoderma guizhouense NJAU4742, however, the differentially regulated cellulases and xylanases were both under the absolute control of the same TgXyr1-mediated pathway. Further analysis showed that Avicel could specifically induce cellulase expression, which supported the existence of an unknown specific regulator of cellulases in strain NJAU4742. The xylanase secretion is very complex, GH10 endoxylanases could only be induced by Avicel, while, other major xylanases were significantly induced by both Avicel and xylan. For GH10 xylanases, an unknown specific regulator was also deduced to exist. Meanwhile, the post-transcriptional inhibition was subsequently suggested to stop the Avicel-induced xylanases secretion, which explained the specifically high xylanase activities when induced by xylan in strain NJAU4742. Additionally, an economical strategy used by strain NJAU4742 was proposed to sense the environmental lignocellulose under the carbon starvation condition, that only slightly activating 4 lignocellulose-degrading genes before largely secreting all 33 TgXyr1-controlled lignocellulases if confirming the existence of lignocellulose components. Conclusions: This study, aiming to explore the unknown mechanisms of plant biomass-degrading enzymes regulation through the combined omics analysis, will open directions for in-depth understanding the complex carbon utilization in filamentous fungi. [ABSTRACT FROM AUTHOR]

Introduction: Actinomycetes are filamentous and gram-positive bacteria living as free-living, saprophyte, and sometimes in symbiosis with plants. These bacteria could be isolated from all ecosystems including soil, water, marine sediments and especially hot waters. Marine actinobacteria are known as the producers of a vast range of secondary metabolites. Any actinobacterial strain has the genetic potential for the production of 10-20 of the secondary metabolites. About 23000 antibiotic types were discovered from microorganisms which according to the estimations, about 10000 types have been isolated from actinobacteria. The secondary metabolites produced by marine actinobacteria have an extensive range of biological activities such as antibacterial, antifungal, anti-cancer, cytotoxic, cytostatic, ant-inflammatory, anti-parasite, anti-malaria, antiviral, anti-oxidant and anti-angiogenesis, etc. Materials and Methods: In the present study, water and sediment samples from the Persian Gulf at the Bushehr Atomic Energy Beach were collected for Actinobacteria isolation. For the cultivation of these samples, 7 culture medium types were used. For the identification of the gathered isolates, morphological properties, biochemical tests, and molecular studies (e.g. PCR) were investigated. Results: Twenty-four isolates of Actinobacteria were isolated from water and sediment samples of the Persian Gulf coast. Eighteen of the isolates have antibacterial activities. Seventy-five persent of the isolates were antibiotic producers and 95% of the gathered substances from these 18 strains had an antibacterial effect against gram-positive bacteria and 60% against gram-negative bacteria. Also, 60% of these substances were effective against both bacteria groups. Discussion and Conclusion: The abundance of marine actinobacteria in new sources of the Persian Gulf and the extension of this sea’s coat indicates the potential capability of this source for investigation in the scope of attaining new antibiotics. [ABSTRACT FROM AUTHOR]

Biosurfactants are produced by important types of microorganisms such as bacteria, yeast, and filamentous fungi and have been used in a variety of industries. Among the 15 crude oil‐degrading fungi, the two molds and one yeast were identified by 18S rDNA sequences as Mucor circinelloides strain SKMC, Fusarium fujikuroi strain DB2, and Rhodotorula mucilaginosa strain SKF2. These strains were isolated from crude oil–contaminated soil, diesel oil–contaminated soil, and activated sludge in the Oil Refinery Plant in Isfahan, Iran, respectively. The yeast strain was identified as a novel crude oil–degrading and biosurfactant‐producing fungi in the presence of (1% v/v) Iranian light crude oil in the minimal salt medium (MSM). The highest amount of the dry weight of produced biosurfactant was measured at 6.2 g L−1. Chemical nature of produced biosurfactant was determined as a surface‐active sophorolipid biosurfactant compound by thin‐layer chromatography, Fourier transform infra‐red spectroscopy, and gas chromatography–mass spectrometry (GC–MS) analysis. The residual hydrocarbons in the MSM were analyzed by GC–MS, and it was shown that octadecane and docosane were eliminated by this novel strain completely. [ABSTRACT FROM AUTHOR]

Microbial proteases constitute one of the most important groups of industrially relevant enzymes. Proline iminopeptidases (PIPs) that specifically release amino-terminal proline from peptides are of major interest for applications in food biotechnology. Proline iminopeptidase has been extensively characterised in bacteria and filamentous fungi. However, no similar reports exist for yeasts. In this study, a protease gene from Glaciozyma antarctica designated as GaPIP was cloned and overexpressed in Escherichia coli. Sequence analyses of the gene revealed a 960 bp open reading frame encoding a 319 amino acid protein (35,406 Da). The purified recombinant GaPIP showed a specific activity of 3561 Umg−1 towards L-proline-p-nitroanilide, confirming its identity as a proline iminopeptidase. GaPIP is a cold-active enzyme with an optimum activity of 30 °C at pH 7.0. The enzyme is stable between pH 7.0 and 8.0 and able to retain its activity at 10–30 °C. Although GaPIP is a serine protease, only 25% inhibition by the serine protease inhibitor, phenylmethanesulfonylfluoride (PMSF) was recorded. This enzyme is strongly inhibited by the presence of EDTA, suggesting that it is a metalloenzyme. The dimeric structure of GaPIP was determined at a resolution of 2.4 Å. To date, GaPIP is the first characterised PIP from yeasts and the structure of GaPIP is the first structure for PIP from eukaryotes. [ABSTRACT FROM AUTHOR]

Ambrosia beetles bore into host trees, and live with fungi symbiotically that serve as a food source. However, it is challenging to directly observe these beetles in the wild. In this study, Euwallacea interjectus (Blandford) (Coleoptera: Curculionidae: Scolytinae), a pest of fig trees in Japan, were reared under artificial conditions to emulate the behavior of ambrosia beetle. Fungi were isolated from the adult females of E. interjectus to identify the species associated with secondary symbiosis. In total, nine filamentous fungi and one yeast were identified using morphological characteristics and DNA sequence data. Neocosmospora metavorans (Hypocreales: Nectriaceae), Fusarium sp. (Hypocreales: Nectriaceae), that is undescribed, and Meyerozyma guilliermondii (Saccharomycetes: Saccharomycetales) (yeast) were isolated more frequently from the head (including from mycangia, the fungus-carrying organ) than from the thorax and abdomen of adult beetles. Neocosmospora metavorans was the dominant species isolated from 12 out of 16 heads at 200 to 3300 CFUs/head, compared to the primary mycangia fungus from wild beetles, i.e., Fusarium kuroshium (Hypocreales: Nectriaceae). Temperature had a marked effect on fungal growth in the three symbiont species. Our results represent a major paradigm shift in understanding beetle–fungal interactions, as they show specific symbiont switching can occur in different nesting places. [ABSTRACT FROM AUTHOR]

The microbial diversity, transformation potential and ability of microorganisms of the microbial mat consortium of the Kucheger thermal spring (Baikal Rift Zone) to generate electricity were studied. High-throughput sequencing showed the predominance of representatives of the Proteobacteria phylum in the microbial mat community (85.5% of the number of classified bacterial sequences). Among Proteobacteria, filamentous sulfur bacteria of the genus Thiothrix are the most numerous (66.1%). In addition, bacteria of the families Rhodocyclaceae (3%) and Comamonadaceae (7.3%) were present in the mat community. The Bacteroidetes phylum was represented by sequences belonging mainly to the Flavobacteriaceae family (6.8%). The sequences of other phyla accounted for no more than 0.5% of the total number of classified sequences. A wide metabolic activity of microorganisms of mat Kucheger-15 was revealed. The high electrogenic ability of microorganisms of the consortium of microbial mats Kucheger-15 in biofuel cells (BFCs) is shown. Mat-based BFCs generated electricity by adding substrates such as peptone, cellulose, starch. Peptone, glucose, tween-80, starch, sodium acetate, and cellulose were used as substrates. Peptone turned out to be the most effective substrate for the production of electricity in BFCs based on Kucheger microbial mat microorganisms. The addition of a mixture of these substrates to the anolyte (the concentration of each of them is 2.5 g/l) made it possible to achieve some increase in energy release (especially the output current) compared to BFC based on each of these substrates separately. The presence of a wide variety of different microorganisms with broad substrate specificity, the ability to function under extreme conditions (high temperature, high pH values), their well-coordinated work and adaptation to each other and to the resulting metabolites, and stability over time allow us to speak of high prospects for the use of hot spring mats in BFC technologies. [ABSTRACT FROM AUTHOR]

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The metagenome of foulings from sulfidic spring "Serovodorodny" (Tatarstan, Russia), where members of the genus Thiothrix was observed, was sequenced. Representatives of the phyla Gammaproteobacteria, Cyanobacteria and Campilobacteriota dominated in the microbial community. The complete genome of Thiothrix sp. KT was assembled from the metagenome. It displayed 93.93–99.72% 16S rRNA gene sequence identity to other Thiothrix species. The average nucleotide identity (ANI) и digital DNA-DNA hybridization (dDDH) showed that the genome designated KT represents a new species within the genus Thiothrix, 'Candidatus Thiothrix sulfatifontis' sp. nov. KT. The taxonomic status has been determined of the strain Thiothrix sp. CT3, isolated about 30 years ago and not assigned to any of Thiothrix species due to high 16S rRNA gene sequence identity with related species (i.e., 98.8–99.4%). The complete genome sequence of strain CT3 was determined. The ANI between CT3 and other Thiothrix species was below 82%, and the dDDH values were less than 40%, indicating that strain CT3 belongs to a novel species, Thiothrix winogradskyi sp. nov. A genome analysis showed that both strains are chemo-organoheterotrophs, chemolithotrophs (in the presence of hydrogen sulfide and thiosulfate) and chemoautotrophs. For the first time, representatives of Thiothrix showed anaerobic growth in the presence of thiosulfate. [ABSTRACT FROM AUTHOR]

Osteoarthritis is a common cause of morbidity and mortality in geriatric gazelles. Propionibacterium australiense has been reported as a cause of systemic granulomas in cattle, but there are no descriptions of this bacteria infecting other species nor causing osteoarthritis, to our knowledge. An 8-y-old, castrated male, sand gazelle ( Gazella leptoceros leptoceros ) was managed for chronic, intermittent, progressive osteoarthritis of the right tarsus. Serial biopsies revealed pyogranulomatous dermatitis with intralesional bacteria. Serial diagnostic imaging identified osseous and soft tissue proliferation with draining tracts. Treatments over 1 y included broad-spectrum antibiotics, anti-inflammatories, joint debridement, and infusion with platelet-rich plasma and stem cells. Despite therapy, lameness persisted, azotemia developed, and subsequently, the animal was euthanized. On postmortem examination, the periarticular tissue of the right tarsus was markedly expanded by pyogranulomas and fibrosis. Histologically, the synovium, joint capsule, and overlying soft tissues were markedly expanded by pyogranulomas and numerous gram-positive and acid-fast-negative filamentous bacteria surrounded by Splendore-Hoeppli material. Within the joint, there was regionally extensive cartilage ulceration, osteonecrosis, osteolysis, and pannus formation. PCR assay of affected formalin-fixed, paraffin-embedded tissue amplified segments of 16S rRNA and β subunit of bacterial RNA polymerase ( rpoB ) genes with 99.7% and 95.6% identity to P. australiense . This bacterium should be considered a differential for chronic pyogranulomatous osteoarthritis in gazelles., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Euglena gracilis is a freshwater flagellate possessing secondary chloroplast of green algal origin. This protist has numerous biotechnological applications such as production of biofuels and pharmaceuticals, and it can be also used for bioremediation of polluted water and wastewater. One of the highest limitations for its large-scale cultivation is that it cannot synthesize vitamins B 1 and B 12 which are expensive and they have to be added to media. This study revealed that E. gracilis can be grown for long time periods without the addition of vitamins B 1 and B 12 in the co-culture containing filamentous fungus Cladosporium westerdijkiae , and bacteria Lysinibacillus boronitolerans and Pseudobacillus badius. Growing of E. gracilis in such co-cultures without the addition of vitamins can dramatically reduce large scale cultivation costs. Moreover, C. westerdijkiae could be used in biotechnology for immobilization and effective harvesting of E. gracilis from big cultivation containers by bioflocculation. • Selected fungus and bacteria supply E. gracilis with vitamins B 1 and B 12. • E. gracilis cells are associated with hyphae of C. westerdijkiae by flagella. • Our co-culture can be used for effective large-scale cultivation of E. gracilis. [ABSTRACT FROM AUTHOR]

Background. Periapical actinomycosis, which is reckoned as a subgroup of cervicofacial actinomycosis, is an uncommon, more indolent, less invasive, and limited type of actinomycosis infection. However, it can be considerably underreported due to the low number of periapical surgical specimens that are submitted for histopathological analysis after excision of the lesion with the preliminary diagnosis of typical periapical infections. It is believed that during root canal treatment, the organisms are displaced from the oral cavity into the periapical regions as a result of failure to establish aseptic techniques which can further result in actinomycosis infections and, in rare instances, lead to more severe events and can even be life-threatening. Case Presentation. We intend to report a case of periapical actinomycosis in a 34-year-old female who presented with the chief complaint of pain and slight mobility of the mandibular right second premolar and first molar with no significant issues in the patient's medical history. Initial orthopantomography revealed a uniloculated, radiolucent lesion engulfing the apices of the aforementioned teeth. An incisional biopsy was then obtained which revealed fragments of fibroconnective tissue including few crushed bone particles severely infiltrated by acute inflammatory cells and some foamy macrophages. The suppurative exudate focally surrounds colonies of filamentous bacteria as round basophilic masses with radial configuration resembling "sulfur granules." Surgical approach consisted of curettage accompanied with peripheral ostectomy and cautious burnishing of the two involved tooth roots. Conclusion. This case report emphasizes the importance of aseptic techniques during endodontic and more invasive treatments, as they can cause penetration of Actinomyces into the periapical region which in some cases can lead to more serious complications and even life-threatening situations. [ABSTRACT FROM AUTHOR]

More than 20% of all Pseudomonas aeruginosa are infected with Pf4-related filamentous phage and although their role in virulence of P. aeruginosa strain PAO1 is well documented, its properties related to therapy are not elucidated in detail. The aim of this study was to determine how phage and antibiotic therapy induce Pf4, whether the released virions can infect other strains and how the phage influences the phenotype of new hosts. The subinhibitory concentrations of ciprofloxacin and mitomycin C increased Pf4 production for more than 50% during the first and sixth hour of exposure, respectively, while mutants appearing after infection with obligatory lytic phage at low MOI produced Pf4 more than four times after 12–24 h of treatment. This indicates that production of Pf4 is enhanced during therapy with these agents. The released virions can infect new P. aeruginosa strains, as confirmed for models UCBPP-PA14 (PA14) and LESB58, existing both episomally and in a form of a prophage, as confirmed by PCR, RFLP, and sequencing. The differences in properties of Pf4-infected, and uninfected PA14 and LESB58 strains were obvious, as infection with Pf4 significantly decreased cell autoaggregation, pyoverdine, and pyocyanin production, while significantly increased swimming motility and biofilm production in both strains. In addition, in strain PA14, Pf4 increased cell surface hydrophobicity and small colony variants' appearance, but also decreased twitching and swarming motility. This indicates that released Pf4 during therapy can infect new strains and cause lysogenic conversion. The infection with Pf4 increased LESB58 sensitivity to ciprofloxacin, gentamicin, ceftazidime, tetracycline, and streptomycin, and PA14 to ciprofloxacin and ceftazidime. Moreover, the Pf4-infected LESB58 was re-sensitized to ceftazidime and tetracycline, with changes from resistant to intermediate resistant and sensitive, respectively. The obtained results open a new field in phage therapy—treatment with selected filamentous phages in order to re-sensitize pathogenic bacteria to certain antibiotics. However, this approach should be considered with precautions, taking into account potential lysogenic conversion. [ABSTRACT FROM AUTHOR]

The mechanism of production of extracellular vesicles (EVs) and their molecular contents are of great interest due to their diverse roles in biological systems and are far from being completely understood. Even though cellular cargo releases mediated by EVs have been demonstrated in several cases, their role in secondary metabolite production and release remains elusive. In this study, this aspect is investigated in detail using Raman microspectroscopic imaging. Considerable evidence is provided to suggest that the release of antibiotic penicillin by the filamentous fungus Penicillium chrysogenum involves EVs. Further, the study also reveals morphological modifications of the fungal body during biogenesis, changes in cell composition at the locus of biogenesis, and major molecular contents of the released EVs. The results suggest a possible general role of EVs in the release of antibiotics from the producing organisms. [ABSTRACT FROM AUTHOR]

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The germplasm bank of economic algae provides biological insurance against environmental changes and pressures for the cultivation industry. However, the red algal free-living conchocelis germplasm of Neopyropia was easily contaminated with filamentous cyanobacteria, which severely affected the growth of Neopyropia germplasm. To date, what and how the filamentous cyanobacteria contaminated Neopyropia germplasm remained unknown. Here, we combined cytological observations with light and electron microscopes and molecular analysis of the 16S rRNA gene to elucidate the pattern of cyanobacteria contamination. Nine filamentous cyanobacteria samples isolated from the Neopyropia germplasm bank were selected. Integrating microscopy observations and phylogenetic analyses of 16S rRNA gene sequences, nine cyanobacteria samples were divided into three groups, including two Leptolyngbya with red pigments (YCR1 and YCR2) and one Nodosilinea with green pigments (YCG3). They had the same asexual reproduction mode, releasing hormogonia to grow new filaments. Due to the high reproductive ability, Leptolyngbya and Nodosilinea were easy to spread in the Neopyropia germplasm. Based on 16S rRNA gene high-throughput sequencing analyses, we found the thallus of Neopyropia (NP1, NP2, and NP3) and surrounding seawater (SW1, SW2, and SW3) were enriched with cyanobacteria, especially with Leptolyngbya and Nodosilinea, indicating the filamentous cyanobacteria contaminated Neopyropia germplasm came from the thallus of Neopyropia or seawater. The results provided a better understanding of the prevention and control of cyanobacteria contamination in the Neopyropia germplasm bank. [ABSTRACT FROM AUTHOR]

Fermentation of various food stuffs by lactic acid bacteria is one of the oldest forms of food biopreservation. Bacterial antagonism has been recognized for over a century, but in recent years, this phenomenon has received more scientific attention, particularly in the use of various strains of lactic acid bacteria (LAB). Certain strains of LAB demonstrated antimicrobial activity against foodborne pathogens, including bacteria, yeast and filamentous fungi. Furthermore, in recent years, many authors proved that lactic acid bacteria have the ability to neutralize mycotoxin produced by the last group. Antimicrobial activity of lactic acid bacteria is mainly based on the production of metabolites such as lactic acid, organic acids, hydroperoxide and bacteriocins. In addition, some research suggests other mechanisms of antimicrobial activity of LAB against pathogens as well as their toxic metabolites. These properties are very important because of the future possibility to exchange chemical and physical methods of preservation with a biological method based on the lactic acid bacteria and their metabolites. Biopreservation is defined as the extension of shelf life and the increase in food safety by use of controlled microorganisms or their metabolites. This biological method may determine the alternative for the usage of chemical preservatives. In this study, the possibilities of the use of lactic acid bacteria against foodborne pathogens is provided. Our aim is to yield knowledge about lactic acid fermentation and the activity of lactic acid bacteria against pathogenic microorganisms. In addition, we would like to introduce actual information about health aspects associated with the consumption of fermented products, including probiotics. [ABSTRACT FROM AUTHOR]

The diversity of photosystem oligomers is essential to understanding how photosynthetic organisms adapt to light conditions. Due to its structural and physiological significance, the assembly of the PSI supercomplex has been of great interest recently in terms of both chloroplast and cyanobacteria. In this study, two novel photosystem I supercomplexes were isolated for the first time from the low light incubated culture of filamentous cyanobacterium Anabaena sp. PCC 7120. These complexes were defined as PSI hexamers and octamers through biochemical and biophysical characterization. Their 77K emission spectra indicated that the red forms of chlorophylls seemed not to be affected during oligomerization. By cryo-EM single-particle analysis, a near-atomic (7.0 Å) resolution structure of a PSI octamer was resolved, and the molecular assemblies of a stable PSI octamer were revealed. [ABSTRACT FROM AUTHOR]

This work was to quantify the superficial growth and the pigmentation of filamentous fungi colonies by effect of an extremely low frequency oscillating magnetic field (OMF-ELF) depending on nutritional status of these microorganisms in two culture media. OMF-ELF of 2 mT by 60 Hz/200 V during 2 h (optimization of an experimental design) was applied at two filamentous fungi strains isolated from indoor environments: Aspergillus niger (hyaline mycelium seen under the optic microscope) and Cladosporium cladosporioides (pigmented mycelium), this latter strain was used as a negative control. The strains were inoculated in Petri dishes with Malt Extract Agar (MEA) and Czapek Dox Agar (CDA), incubated at 30°C and photographs were taken every 4 hours for 10 days. The area (superficial growth) and color intensity (pigmentation) of these colonies were evaluated by digital images processing (DIP) using MatLab®. The stimulating effect of OMF-ELF on the cellular metabolism of both fungal strains was demonstrated, with an increase of the superficial growth and a greater variation in pigmentation (indicative of sporulation by conidiogenesis) in CDA until reaching values of spores similar to when there are enough nutrients (MEA). The predictive mathematical model obtained by optimization of the experimental design to predict the growth of Aspergillus niger colony was validated with the algorithm implemented for the DIP. It was concluded that the OMF-ELF stimulated the metabolism of the studied fungal strains independently of the nutrients in the culture media and that the DIP is a precise technique to quantify the macroscopic phenomena that occur due to magnetobiological effects at the cellular level. [ABSTRACT FROM AUTHOR]

In order to research the treatment effect of integrated process on printing and dyeing wastewater, the AMC/UASB-PBG/MBBR biochemical process was used to treat printing and dyeing wastewater(COD 2 300～3 500 mg/L, ammonia nitrogen 12～25 mg/L, chromaticity 256～512 times)from a factory in Xianyang, and the effect of PANI/PVA adsorbent on the treatment of ammonia nitrogen and chromaticity in the effluent of the biochemical process was studied. The results show that the wastewater COD removal rate reached 80%, the chromaticity decreased from 256 to 64 times, and the effluent ammonia nitrogen mass concentration was 9.2 mg/L; the ammonia nitrogen mass concentration decreased to 5.7 mg/L and the chromaticity decreased from 64 to 16 times after the biochemical process effluent was treated with the homemade adsorbent; SEM revealed that the surface of mature AMC anaerobic granular sludge mainly aggregated cocci, bacilli and filamentous bacteria, and the surface and interior of PBG aerobic carrier were enriched with a large number of filamentous bacteria and cocci. The two biological carriers had good microbial enrichment ability, which could effectively improve the degradation capacity of the system organic matter. The optical microscope revealed the proesence of mircoorganisms such as rotifers and paramecium in the PBG carrier biofilm, and a long food chain was formed. After 42 d of actural operation in production, the AMC/UASB-PBG/MBBR biochemical process combined with PANI/PVA adsorbent has a good treatment effect. [ABSTRACT FROM AUTHOR]

Simple Summary: Antimicrobial resistance (AMR) is a pressing issue worldwide that must be addressed swiftly. It is driven by spontaneous evolution, bacterial mutation, and the dissemination of resistant genes via horizontal gene transfer. Researchers are working on many novel targets, which can become a pathway to inhibit harmful bacteria. Filamentous Thermosensitive mutant-Z (Fts-Z) is one such bacterial target that has gained popularity amongst scientists due to its conserved nature in bacteria and absence in eukaryotes. The aim of this work was to review the Fts-Z mechanism of action along with current studies on natural inhibitors for Fts-Z. Antibiotic resistance is a major emerging issue in the health care sector, as highlighted by the WHO. Filamentous Thermosensitive mutant Z (Fts-Z) is gaining significant attention in the scientific community as a potential anti-bacterial target for fighting antibiotic resistance among several pathogenic bacteria. The Fts-Z plays a key role in bacterial cell division by allowing Z ring formation. Several in vitro and in silico experiments have demonstrated that inhibition of Fts-Z can lead to filamentous growth of the cells, and finally, cell death occurs. Many natural compounds that have successfully inhibited Fts-Z are also studied. This review article intended to highlight the structural–functional aspect of Fts-Z that leads to Z-ring formation and its contribution to the biochemistry and physiology of cells. The current trend of natural inhibitors of Fts-Z protein is also covered. [ABSTRACT FROM AUTHOR]

Tyzzer disease (TD) is caused by Clostridium piliforme, a gram-negative and obligate intracellular bacterium. The disease occurs in multiple species. A triad of lesions, namely colitis, hepatitis, and myocarditis, is described in cases of TD in some species, such as rats and mice. We carried out a retrospective analysis of 25 equine cases with a diagnosis of TD; 24 of 25 cases occurred in foals <45 d old; the remaining foal was 90 d old. There were 12 males and 12 females; no sex information was available for one foal. The affected breeds were Quarter Horse, Thoroughbred, Arabian, Paint, and Hanoverian. Most of the cases (19 of 25) occurred in the spring. There were 9 cases of sudden death; the remaining animals had diarrhea, fever, distended abdomen, depression, weakness, non-responsiveness, and/or recumbency. Gross findings included icterus, hepatomegaly with acinar pattern, serosal hemorrhages, pulmonary edema, and/or fluid content in small and large intestine. Microscopically, all foals had severe, multifocal, necrotizing hepatitis. Necrotizing lymphohistiocytic colitis was observed in 10 of 25 foals, and multifocal necrotizing myocarditis was found in 8 of 25. Gram-negative, Steiner-positive, intracytoplasmic filamentous bacteria were observed in hepatocytes, enterocytes, and myocardiocytes, respectively. PCR detected C. piliforme DNA in the liver (24 of 24), colon (20 of 24), and heart (5 of 25). Our results indicate that necrotic hepatitis is the hallmark of TD in horses; the so-called triad of lesions is not a consistent characteristic of the disease in this species. [ABSTRACT FROM AUTHOR]

The NF‐κB transcription factor c‐Rel plays a crucial role in promoting and regulating immune responses and inflammation. However, the function of c‐Rel in modulating the mucosal immune system is poorly understood. T follicular helper (Tfh) cells and IgA production in gut‐associated lymphoid tissues (GALT) such as Peyer's patches (PPs) are important for maintaining the intestinal homeostasis. Here, c‐Rel was identified as an essential factor regulating intestinal IgA generation and function of Tfh cells. Genetic deletion of c‐Rel resulted in the aberrant formation of germinal centers (GCs) in PPs, significantly reduced IgA generation and defective Tfh cell differentiation. Supporting these findings, the Ag‐specific IgA response to Citrobacter rodentium was strongly impaired in c‐Rel‐deficient mice. Interestingly, an excessive expansion of segmented filamentous bacteria (SFB) was observed in the small intestine of animals lacking c‐Rel. Yet, the production of IL‐17A, IgA, and IL‐21, which are induced by SFB, was impaired due to the lack of transcriptional control by c‐Rel. Collectively, the transcriptional activity of c‐Rel regulates Tfh cell function and IgA production in the gut, thus preserving the intestinal homeostasis. [ABSTRACT FROM AUTHOR]

Rotation is part of our everyday lives. For most of human history, rotation was considered a uniquely human invention, something beyond the anatomical capabilities of organisms. In 1973, Howard Berg made the audacious proposal that the common gut bacterium Escherichia coli swims by rotating helical flagellar filaments. In 1987, Paul Boyer suggested that the FoF1 ATP synthase of E. coli is also a rotary device. Now we know that rotating nanomachines evolved independently at least three times. They power a wide variety of cellular processes. Here, the study of flagellar rotation in E. coli is briefly summarized. In 2020, the Cryo-EM structure of the MotAB stator element of the bacterial flagellum was described. The structure strongly suggests that the MotAB stator rotates to drive flagellar rotation. Similar motors are coupled to other diverse processes. The following articles in this issue review the current knowledge and speculation about rotating biological nanomachines. [ABSTRACT FROM AUTHOR]

A cyanophage PaV-LD, previously isolated from harmful filamentous cyanobacterium Planktothrix agardhii , was sequenced, and co-expression of its two ORFs in tandem, ORF123 and ORF124, inhibited growth on the model cyanobacterium Synechocystis sp. PCC6803 cells. However, the mechanism of action of ORF123 and ORF124 alone remains to be elucidated. In this study, we aimed to study the individual function of ORF123 or ORF124 from PaV-LD. Our data showed that the ORF123 encoded an endopeptidase, which harbored an M23 family peptidase domain and a transmembrane region. The expression of the endopeptidase in Escherichia coli alone revealed that the protein exhibited remarkable bacteriostatic activity, as evidenced by observation of growth inhibition, membrane damage, and leakage of the intracellular enzyme. Similarly, the holin, a membrane-associated protein encoded by the ORF124, showed weak bacteriostatic activity on E. coli. Moreover, deletion mutations indicated that the transmembrane domains of endopeptidase and holin were indispensable for their bacteriostatic activity. Meanwhile, the bacteriostatic functions of endopeptidase and holin on cyanobacteria cells were confirmed by expressing them in the cyanobacterium Synechocystis sp. PCC6803. Collectively, our study revealed the individual role of endopeptidase or holin and their synergistic bacteriolytic effect, which would contribute to a better understanding of the lytic mechanism of cyanophage PaV-LD. [ABSTRACT FROM AUTHOR]

Phagemid particles based on the Neisseria gonorrhoeae filamentous phage NgoΦ6 were used as a vaccine delivery system. We demonstrate that the host proteins incorporated into/associated with these particles can be encoded by chromosomal genes of the host bacterium or from plasmids able to replicate as an autonomous entity in the phagemid host. Phagemid particles were prepared from three types of cells, namely, Salmonella enterica ser. Typhimurium [pBSKS::Φ6fm(ST)] containing phagemid genome as an autonomous plasmid, Haemophilus influenzae Rd containing phagemid [pBSKS::Φ6fm(Hin)] integrated into the chromosome, and S. enterica ser. Typhimurium [pMPMT6::Φ6fm(ST)] containing an additional plasmid, pE1 HCV, encoding the Hepatitis C virus envelope glycoprotein E1. Approximately 200 μg of purified phage particles was used to immunize rabbits. The phagemid particles prepared from these three strains all elicited a large amount of IgG antibodies that were able to recognize bacterial host cells and proteins, as determined by ELISA and FACS analysis. The amount of specific anti- S. enterica ser. Typhimurium, anti- H. influenzae , and anti-E1 HCV antibodies elicited by vaccination was 170 μg/ml for anti- Salmonella , 80 μg/ml for anti- H. influenzae , and 65 μg/ml for anti-E1 HCV. Taken in toto, these data suggest that classical phage display methods have underestimated the potential for filamentous phage as a novel immunogen delivery system. [ABSTRACT FROM AUTHOR]

The origin of pisoids in a diversity of environments has been recently discussed. While traditionally considered physico‐chemical sedimentary products developed in turbulent environments, or even grown in situ, new results show that microbes may influence their development. In the Terma Los Hornos travertine system, two types of actively forming pisoids were recognized: (i) laminated pisoids with a concentrically laminated crust surrounding a nucleus; and (ii) dendriform radial pisoids with no distinct nucleus. Laminated pisoids form in turbulent pools at the base of waterfalls, while dendritic pisoids develop within small depressions between terracettes, and they can occur superposed as a result of episodic transport and recycling within the travertine system (for example, dendritic textures as nucleus of laminated pisoids). The laminated pisoids are characterized by laterally constant laminae thickness with high inheritance and low amounts of randomly distributed organic matter and microbial remains, suggesting a predominantly abiogenic origin. In contrast, the dendritic pisoids exhibit an intimate relationship with diatoms and filamentous bacteria suggesting a stronger biotic influence in their formation. Thus, both abiogenic and biogenic carbonate structures can coexist in the same hydrothermal system. Pisoids found in the stratigraphic record of Terma Los Hornos allowed to test the preservation potential of the primary signals and reconstructing early diagenetic overprints. [ABSTRACT FROM AUTHOR]

Marine-derived Aspergillus terreus produces a variety of structurally novel secondary metabolites, most of which show unique biological activities. However, the lack of efficient genetic tools limits the discovery of new compounds, the elucidation of involved biosynthesis mechanism, as well as the strain engineering efforts. Therefore, in this study, we first established both an effective PEG-mediated chemical transformation system of protoplasts and an electroporation system of conidia in a marine-derived fungus A. terreus RA2905. To overcome the insensitivity of RA2905 to fungicides, the uracil auxotrophy strain (pyrG gene deletion mutant, ΔpyrG) was constructed using PEG-mediated transformation system, and using ΔpyrG as the genetic background, the methyltransferase gene laeA-overexpression transformants were further constructed through both PEG- and electroporation-mediated transformations, which showed enhanced terrein production. Besides, in this study, an efficient CRISPR/Cas9 genome-editing system was established for the first time in A. terreus, and a higher gene deletion efficiency of 71% for APSES transcription factor gene stuA could be achieved when using short homologous arms compared with conventional long homologous ones. In addition, using a non-integrative Cas9 plasmid, another efficient and marker-free genome-editing system was established, which allowing repeatable and unlimited genetic manipulation in A. terreus. Using the marker-free genome-editing system, we successfully developed the ΔpyrGΔku70 double-deletion mutant in RA2905, which could further improve gene deletion efficiency. In conclusion, efficient genetic manipulation systems along with a variety of functional mutants were developed in this study, which would significantly expedite both theoretical and applied researches in not only A. terreus but also other marine-derived filamentous fungi. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central European Agriculture is the property of Journal of Central European Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• A functional c-di-GMP network is present in cyanobacterium Arthrospira. • Five c-di-GMP-related genes show a conserved distribution in genus Arthrospira. • Overproduction of Adc1 promotes EPS production of Arthrospira. • Overproduction of Adc1 promotes aggregation of Arthrospira filaments. Cyclic diguanosine monophosphate (c-di-GMP) is a second messenger in bacteria that regulates multiple biological functions, including biofilm formation, virulence, and intercellular communication. However, c-di-GMP signaling is virtually unknown in economically important filamentous cyanobacteria, Arthrospira. In this study, we predicted 31 genes encoding GGDEF-domain proteins from A. platensis NIES39 as potential diguanylate cyclases (DGCs). Phylogenetic distribution analysis showed five genes (RS09460, RS04865, RS26155, M01840, and E02220) with highly conserved distribution across 25 Arthrospira strains. Adc1 encoded by RS09460 was further characterized as a typical DGC. By establishing the genetic transformation system of Arthrospira , we demonstrated that the overexpression of Adc1 promoted the production of extracellular polymeric substances (EPS), which in turn caused the aggregation of filaments. We also confirmed that RS04865 and RS26155 may encode active DGCs, while enzymatic activity assays showed that proteins encoded by M01840 and E02220 have phosphodiesterase (PDE) activity. Meta-analysis revealed that the expression profiles of RS09460 and RS04865 were unaffected under 31 conditions, suggesting that they may function as conserved genes in maintaining the basal level of c-di-GMP in Arthrospira. In summary, this report will provide the basis for further studies of c-di-GMP signal in Arthrospira. [ABSTRACT FROM AUTHOR]

In this study, the effluent from recycled paper mill was treated using a combined ozone (O 3) and biological aerated filter (BAF) process. Key operational parameters such as ozone dosage, pH, hydraulic retention time (HRT), volume load and gas-to-water ratio were optimized. Under optimal conditions, with a total ozone dosage of 100 g/m, a gas-to-water ratio of 4:1, and an HRT of 3.0 hours in the BAF, the chemical oxygen demand (COD) and chroma of the treated wastewater were reduced to 44–55 mg/L and 2–4 PCU, achieving removal efficiencies of 70 % and 95 %, respectively. The discharge effluent not only satisfy the new discharge standard of China (GB3544–2008), but also can be used as recycling water. Additionally, the treatment cost of wastewater was ca. 1.3 ¥/m3 in pilot-scale test, significantly decreasing the cost. Ozone pretreatment has a significant effect on wastewater decolorization by disrupting the molecular chemical structure of pollutants, which increase the biochemical properties of biofilm and is beneficial to the sequential BAF treatment. The sludge in the O 3 /BAF system exhibited increased biomass with minimal filamentous bacteria and higher dehydrogenase activity, confirming stable and robust bacterial growth. GC-MS analysis revealed substantial reduction in pollutant content and diversity post-treatment, although the recalcitrant compound (Z)-13-docosenamide remained relatively high, decreasing from 27.37 % to 21.14 %. The mechanism of the O 3 /BAF process for the pollutant degradation were also proposed. This study demonstrated that a combination of ozone and fixed biofilm treatment is an efficient and cost-effective treatment, providing the theory and practical applicability for the industrial wastewater. • The operational parameter of O 3 /BAF system for the recycled paper mill wastewater treatment was investigated. • Integrated O 3 /BAF process was effective for the pollutant removal with low treatment cost. • The biofilm was mainly composed by Proteobacteria, Bacteroidota, Desulfobacterota , and Chloroflexi. • Most of the pollutants were degraded after the O 3 /BAF process. [ABSTRACT FROM AUTHOR]

The microbialites identified in the Kuwait Formation (also known as the Kuwait Group) at the Jal Az-Zor escarpment were largely misclassified as calcrete beds. Through detailed geological field observations, five distinct microbial beds have been identified and are found to occur at the end of each depositional cycle. Over these cycles, three main facies have been identified; these are bioturbated cross-bedding, calcareous sandstones, and microbial facies. The combination of field and petrographic analyses indicates that these sequences are dominated by siliciclastic facies, with microbial facies primarily manifesting as thrombolites or laminites, with the former being more common. Mineralogical analysis of the microbial facies indicate that over 60% of this facies is composed of calcite, and energy dispersive spectroscopy measured a significant percentage of organic carbon that reached up to 39.3% wt. Scanning electron microscope imagery of the microbial facies identified filamentous bacteria and flagellates as the principal constituents of these microbial assemblages. The bioturbated cross-bedding facies is found to be deposited in an estuarine central bay, the calcareous sandstone facies is deposited in an estuary mouth bar system that transitions laterally into a shoreface setting, and the microbial facies is deposited in a peritidal setting. Strontium isotope (87Sr/86Sr) dating of the five microbial beds indicates that these beds were deposited at 33.99 Ma, 32.6 Ma, 31.5 Ma, 30 Ma, and 29 Ma, respectively, suggesting that the associated sequences are of a Rupelian 3rd order hierarchy. Our analysis correlates the Jal Az-Zor sequences with New Jersey's Oligocene oxygen isotope sequence boundaries and the La2004 obliquity nodes, suggesting a continued uplift rate during the Rupelian age at the studied area. This article challenges the assumption that the Oligocene success is absent in Kuwait and the surrounding region, opening the door for further assessment of these deposits. • The average depositional duration of each of the Kuwait Formation exposed sequences is found to be 1.2 Ma. • Identified three facies: bioturbated cross bedding, calcareous sandstones, and microbial facies in a marginal marine setting. • Microbial facies contain over 60% calcite, up to 39.3% organic carbon, mainly thrombolites and laminites. • Strontium isotope dating of microbial beds indicates a Rupelian 3rd order sequence hierarchy. • The microbial beds are correlatable with the global New Jersey's Oligocene oxygen isotope sequence boundaries. [ABSTRACT FROM AUTHOR]

[Display omitted] • Activated sludge bulking was rapidly controlled by adding EBPR-AS to BAS reactor. • Aerobic granulation of BAS was promoted by adding EBPR-AS and reducing settling time. • Filamentous growth was inhibited in BAS reactor by activating EBPR activity. • Slow-growing organisms were enriched by adding EBPR-AS, promoting BAS granulation. • The increase in PN/PS ratio in EPS contributed to aerobic granulation of BAS. This study investigated the effects of enhanced biological phosphorus removal (EBPR) on rapid sludge bulking control and fast aerobic granular sludge (AGS) formation by adding 20 % of EBPR activated sludge to the bulking activated sludge (BAS) reactor. The results indicate that activating EBPR activity swiftly improved BAS settleability within 16 days, thus resolving sludge bulking issues. Subsequently, a settling time-based selection was employed, resulting in the BAS granulation within another 16 days. The rapid achievement of EBPR activity improved the BAS settleability and facilitated the formation of sludge aggregates, thereby expediting BAS granulation. Inhibition of filamentous bacteria and enrichment of slow-growing organisms contributed to both sludge bulking control and aerobic granulation. Furthermore, the increase in proteins/polysaccharides ratio facilitated the granulation process. Additionally, total nitrogen removal increased from 59.4 % to 71.7 % because of the mature AGS formation. This study provided an approach to simultaneously control sludge bulking and promote aerobic granulation. [ABSTRACT FROM AUTHOR]

Induction of commensal-specific immunity contributes to tissue homeostasis, yet the mechanisms underlying induction of commensal-specific B cells remain poorly understood in part due to a lack of tools to identify these cells. Using phage display, we identified segmented filamentous bacteria (SFB) antigens targeted by serum and intestinal antibodies and generated B cell tetramers to track SFB-specific B cells in gut-associated lymphoid tissues. We revealed a compartmentalized response in SFB-specific B cell activation, with a gradient of immunoglobulin A (IgA), IgG1, and IgG2b isotype production along Peyer's patches contrasted by selective production of IgG2b within mesenteric lymph nodes. V(D)J sequencing and monoclonal antibody generation identified somatic hypermutation driven affinity maturation to SFB antigens under homeostatic conditions. Combining phage display and B cell tetramers will enable investigation of the ontogeny and function of commensal-specific B cell responses in tissue immunity, inflammation, and repair. [Display omitted] • Phage display screening identifies immunogenic commensal antigens • B cell antigen tetramers enable identification of SFB-specific B cells • SFB-specific B cells display anatomically compartmentalized effector functions • Affinity maturation of SFB-specific B cells occurs under homeostatic conditions Adaptive immunity to commensal microbes promotes tissue homeostasis, immunity, and repair, but approaches to identify commensal-specific B cell responses are lacking. Verma et al. utilize phage display screening and subsequent generation of B cell tetramers to identify anatomical compartmentalization of SFB-specific B cell responses in gut-associated lymphoid tissues. [ABSTRACT FROM AUTHOR]