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Organisms display an immense variety of shapes, sizes, and reproductive strategies. At microscopic scales, bacterial cell morphology and growth dynamics are adaptive traits that influence the spatial organization of microbial communities. In one such community--the human dental plaque biofilm--a network of filamentous Corynebacterium matruchotii cells forms the core of bacterial consortia known as hedgehogs, but the processes that generate these structures are unclear. Here, using live-cell time-lapse microscopy and fluorescent D-amino acids to track peptidoglycan biosynthesis, we report an extraordinary example of simultaneous multiple division within the domain Bacteria. We show that C. matruchotii cells elongate at one pole through tip extension, similar to the growth strategy of soil-dwelling Streptomyces bacteria. Filaments elongate rapidly, at rates more than five times greater than other closely related bacterial species. Following elongation, many septa form simultaneously, and each cell divides into 3 to 14 daughter cells, depending on the length of the mother filament. The daughter cells then nucleate outgrowth of new thinner vegetative filaments, generating the classic "whip handle" morphology of this taxon. Our results expand the known diversity of bacterial cell cycles and help explain how this filamentous bacterium can compete for space, access nutrients, and form important interspecies interactions within dental plaque. [ABSTRACT FROM AUTHOR]

The glycoside hydrolase family 3 (GH3) β-glucosidases from filamentous fungi are crucial industrial enzymes facilitating the complete degradation of lignocellulose, by converting cello-oligosaccharides and cellobiose into glucose. Understanding the diverse domain organization is essential for elucidating their biological roles and potential biotechnological applications. This research delves into the variability of domain organization within GH3 β-glucosidases. Two distinct configurations were identified in fungal GH3 β-glucosidases, one comprising solely the GH3 catalytic domain, and another incorporating the GH3 domain with a C-terminal fibronectin type III (Fn3) domain. Notably, Streptomyces filamentous bacteria showcased a separate clade of GH3 proteins linking the GH3 domain to a carbohydrate binding module from family 2 (CBM2). As a first step to be able to explore the role of accessory domains in β-glucosidase activity, a screening system utilizing the well-characterised Aspergillus niger β-glucosidase gene (bglA) in bglA deletion mutant host was developed. Based on this screening system, reintroducing the native GH3-Fn3 gene successfully expressed the gene allowing detection of the protein using different enzymatic assays. Further investigation into the role of the accessory domains in GH3 family proteins, including those from Streptomyces, will be required to design improved chimeric β-glucosidases enzymes for industrial application. [ABSTRACT FROM AUTHOR]

hermodynamics has predicted many different kinds of microbial metabolism by determining which pairs of electron acceptors and donors will react to produce an exergonic reaction (a negative net change in Gibbs free energy). In energy-limited environments, such as the deep subsurface, such an approach can reveal the potential for unexpected or counter-intuitive energy sources for microbial metabolism. Up until recently, these thermodynamic calculations have been carried out with the assumption that chemical species appearing on the reactant and product side of a reaction formula have a constant concentration, and thus do not count towards net concentration changes and the overall direction of the reaction. This assumption is reasonable considering microorganisms are too small (~1 μm) for any significant differences in concentration to overcome diffusion. However, recent discoveries have demonstrated that the reductive and oxidative halves of reactions can be separated by much larger distances, from millimetres to centimetres via conductive filamentous bacteria, mineral conductivity, and biofilm conductivity. This means that the concentrations of reactants and products can indeed be different, and that concentration differences can contribute to the net negative change in Gibbs free energy. It even means that the same redox reaction, simultaneously running in forward and reverse, can drive energy conservation, in an ElectroMicrobiological Concentration Cell (EMCC). This paper presents a model to investigate this phenomenon and predict under which circumstances such concentration-driven metabolism might take place. The specific cases of oxygen concentration cells, sulfide concentration cells, and hydrogen concentration cells are examined in more detail. [ABSTRACT FROM AUTHOR]

Compost is a natural and sustainable way to improve soil fertility and enhance plant growth. Moringa leaves have high mineral, cytokinin, and vitamin content which are useful for growth so that they can be used as organic fertilizer. Azotobacter and Streptomyces are from soil and have many biological activities. This study aimed to detect the importance of bioagents formula with Moringa Compost (MC) to enhance plant growth in poor sterile soil and plants were irrigated with half strength of Hoagland nutrient solution. Moringa leaves were collected and cleaned, and organic compost was prepared and analyzed for microbial and chemical composition. The prepared MC was rich in nitrogen and minerals and had high content of bacteria and fungi. The two bioagents used were isolate MB5 and MB11 which were characterized and molecular identified as Azotobacter chroococcum MB5 and Streptomyces griseus MB11. The free-living A. chroococcum can fix atmospheric nitrogen while Streptomyces is a filamentous bacterium with a high ability to produce secondary metabolites. The addition of 20% MC to soil increased soil EC and microbial counts compared to MC-free soil. Moreover, inoculation of soil with either AZ or ST increased the microbial counts and soil EC and the clearest increase was in the case of inoculation of soil with MC+AZ+ST. It also found that MC extract alone with the bacterial filtrates increases seed germination of Phaseolus vulgaris L. (common bean), which is a herbaceous annual worldwide plant, grown for its edible dry seeds or green unripe pods. In this regard, inoculation of soil with inoculum of both A. chroococcum MB5, and S. griseus MB11, in the presence of MC has the most pronounced effect and enhances both the growth, fresh and dry weights, leaf number, plant height, and root length of P. vulgaris grown under greenhouse conditions for one month and chemical content of the plant protein carbohydrates, P, N, Ca++ and K+. In conclusion, the combined application A. chroococcum MB5 and S. griseus MB11, as a biofertilizers with Moringa compost is recommended to enhance P. vulgaris growth. The use of these biofertilizers can reduce the use of chemical fertilizers, which can have detrimental effects on soil and the environment. Therefore, further research on the inoculation and application of these microorganisms with MC is essential for sustainable agriculture. [ABSTRACT FROM AUTHOR]

We investigated suitable culture conditions for the production of the blue pigment phycocyanin (PC) from the unique filamentous cyanobacteria Pseudanabaena sp. ABRG5-3 and Limnothrix sp. SK1-2-1. White, green, or red LED irradiation at 30 μmol photons/m2/s was effective for phycocyanin production when compared with Arthrospira platensis (Spirulina) sp. NIES-39, which is generally grown under high light irradiation. To investigate the safety of the cyanobacteria, ABRG5-3 cells were subjected to Ames (reverse mutation) tests and single oral-dose rat studies, which revealed non-mutagenic and non-toxic properties. When three purified phycocyanins (abPC, skPC, and spPC) were subjected to agarose gel electrophoresis, they showed different mobility, indicating that each phycocyanin has unique properties. abPC exhibited strong antiglycation activities as novel function. • We assessed cultivation conditions and phycocyanin production of 3 cyanobacteria. • We tested various light irradiation conditions in terms of quality and intensity. • We found that ABRG5-3 cells are non-mutagenetic and non-toxic. • Each phycocyanin has unique properties depending on bacterial species. • The phycocyanins showed strong antiglycation activity. [ABSTRACT FROM AUTHOR]

Cable bacteria are filamentous bacteria that couple the oxidation of sulfide in sediments to the reduction of oxygen via long-distance electron transport over centimeter distances through periplasmic wires. However, the capability of cable bacteria to perform extracellular electron transfer to acceptors, such as electrodes, has remained elusive. In this study, we demonstrate that living cable bacteria actively move toward electrodes in different bioelectrochemical systems. Carbon felt and carbon fiber electrodes poised at +200 mV attracted live cable bacteria from the sediment. When the applied potential was switched off, cable bacteria retracted from the electrode. qPCR and scanning electron microscopy corroborated this finding and revealed cable bacteria in higher abundance present on the electrode surface compared with unpoised controls. These experiments raise new possibilities to study metabolism of cable bacteria and cultivate them in bioelectrochemical devices for bioelectronic applications, such as biosensing and bioremediation. [ABSTRACT FROM AUTHOR]

In this study, the antibacterial activity of 10 honeys at three concentrations 50%, 25%, and 12.5% was tested against two G- and two G+ strains, also the microbiological quality of the honeys in terms of the representation of total count of bacteria, coliforms, yeasts, and filamentous fungi was evaluated, and micromycetes to the species level were identified. Antibacterial activity of the honeys was assayed using well diffusion method, determination of microbial groups by the pour plate method and diversity of mycobiota in honey according to macro- and micromorphological characteristics. Results showed the antibacterial effects of Slovak honey collected from the Spiš region, against bacterial strains Escherichia coli, Pseudomonas fluorescens, Enterococcus faecalis, and Staphylococcus aureus, which are among the most common bacteria responsible for nosocomial infections. We found that honeydew honey was very effective against E. coli and S. aureus, rapeseed honey against P. fluorescens, and mixed honey (no. 10) against E. faecalis. Staphylococcus aureus was the most susceptible bacteria tested for all honeys. The presence of both yeasts and molds was detected in 3 honey samples at concentrations ranging from <4x101 to 3.6x101 CFU/g, while the total count of bacteria was detected in 9 samples at concentrations ranging from 2.3x101 to 3.6x102 CFU/g (in 1 sample, the occurrence of microorganisms was not recorded even at the lowest dilution of 10-1). Coliforms were not isolated. A total of 3 strains belonging to the Aspergillus section Nigri were identified. The microbiological analyses of the samples indicates that the honeys were produced, processed and stored in accordance with the rules of good hygiene practice. [ABSTRACT FROM AUTHOR]

Sulfidic caves support diverse and abundant subterranean communities, including numerous endemic species and complex food webs, though the full extent of species diversity and resource utilization in these ecosystems remains largely unexplored. This paper presents the results of biological surveys conducted from 2023 to 2024 in Sulfur Cave, located in the Vromoner Canyon on the Greek–Albanian border, focusing on microbial, vertebrate, and invertebrate communities and investigating the structure of the subterranean food web. The microbial communities from the different biofilms are dominated by chemosynthetic sulfur-oxidizing microorganisms, specifically filamentous bacteria such as Thiotrix and Beggiatoa. Two species of fish, an eel (Anguilla sp.) and a Cyprinid (Alburnoides sp.), and six bat species from three families (Rhinolophidae, Miniopteridae, and Vespertilionidae) were documented. The invertebrate fauna includes five aquatic species, 25 terrestrial species, and four amphibiotic species. Among these, eight species are endemic, and seven species exhibit troglomorphic traits. Stable isotope analysis showed light carbon and nitrogen values for the terrestrial and aquatic invertebrates, suggesting that subterranean communities rely on food produced in situ by chemoautotrophic microorganisms. Our results identified cave areas of significant biological relevance and provided reference data to inform conservation actions aimed at preserving the biodiversity of this sulfidic cave. [ABSTRACT FROM AUTHOR]

The vertical stratification of oxygen concentration in deep reservoirs impacts nutrient cycling and ecosystem biodiversity. The Serra da Mesa reservoir, the largest in Brazil, was studied to evaluate the structure and production of the prokaryote community at five depths. Using 3H leucine incorporation and fluorescent in situ hybridization (FISH), the study focused on different depths near the dam, particularly within the euphotic zone. The water column was characterized into oxic, transitional, and hypoxic layers based on dissolved oxygen concentration. The highest densities and biomasses of prokaryotes were found at the euphotic zone's depth limit, where bacterial production was low, suggesting inactive or slow-growing bacteria. Cell size differences and filamentous bacteria presence near the surface were observed, likely due to varying predation pressures. Prokaryote community composition differed across depths. At the subsurface level, with high dissolved organic carbon, alphaproteobacteria, betaproteobacteria, and Cytophaga–Flavobacter had similar densities, but the lowest bacterial biomass was recorded. The highest dissolved oxygen concentration depth had the lowest bacterial density, dominated by alphaproteobacteria and gammaproteobacteria. The study revealed that prokaryotic community structure and production vary with depth, indicating that microbial participation in layer dynamics is differentiated, with variations in abundance and distribution linked to oxygen concentrations. [ABSTRACT FROM AUTHOR]

Segmented filamentous bacteria (SFB) are members of the commensal intestinal microbiome. They are known to contribute to the postnatal maturation of the gut immune system, but also to augment inflammatory conditions in chronic diseases such as Crohn's disease. Living primary tissue slices are ultrathin multicellular sections of the intestine and provide a unique opportunity to analyze tissue‐specific immune responses ex vivo. This study aimed to investigate whether supplementation of the gut flora with SFB promotes T helper 17 (Th17) cell responses in primary intestinal tissue slices ex vivo. Primary tissue slices were prepared from the small intestine of healthy Taconic mice with SFB‐positive and SFB‐negative microbiomes and stimulated with anti‐CD3/CD28 or Concanavalin A. SFB‐positive and ‐negative mice exhibited distinct microbiome compositions and Th17 cell frequencies in the intestine and complex microbiota including SFB induced up to 15‐fold increase in Th17 cell‐associated mediators, serum amyloid A (SAA), and immunoglobulin A (IgA) responses ex vivo. This phenotype could be transmitted by co‐housing of mice. Our findings highlight that changes in the gut microbiome can be observed in primary intestinal tissue slices ex vivo. This makes the system very attractive for disease modeling and assessment of new therapies. [ABSTRACT FROM AUTHOR]

Strain C29T, a Gram-staining-negative, straight rod occurring singly, in pairs or short chains, was isolated from floating filamentous biomass of the Uruguay River. The strain was catalase and oxidase positive, chemoorganotrophic, strictly aerobic, non-motile, and grew at pH 6.0–9.0, 15–45 °C, and 0–0.5% (w/v) NaCl. Polyhydroxybutyrate was accumulated in nutrient-limited conditions. Phylogenetic analysis based on the 16S rRNA gene revealed that strain C29T had the highest sequence similarity with Leptothrix discophora SS-1T (97.82%), Ideonella livida TBM-1T (97.82%), Vitreoscilla filiformis L1401-2T (97.52%), Sphaerotilus sulfidivorans D-501T (97.50%) and Sphaerotilus natans DSM 6575T (97.46%). Other type strains with validly published names had similarities below 97.46%. Further phylogenomic analysis showed that strain C29T was affiliated to the family Sphaerotilaceae. Average nucleotide identity (ANI) and in silico DNA–DNA hybridization (dDDH) values with its phylogenetic relatives were lower than 91 and 41%, respectively, revealing that strain C29T represented a new species. The DNA G + C content of strain C29T was 70.9%. The annotation of the genome of the novel strain shows it possessed genes for the degradation of aromatic compounds. It also contained genes that encode sigma factors involved in response regulation of stress resistance, which is an important function for adaptation and survival in natural niches. Based on the results of the phylogenetic and phenotypic analyses, we propose that strain C29T represents a novel species, for which the name Sphaerotilus uruguayifluvii sp. nov. is proposed. The type strain is C29T (= CCM 9043T = DSM 113250T). [ABSTRACT FROM AUTHOR]

Soft drinks are industrial intermediate chemicals found in wastewater and are among the most significant environmental pollutants. Up-flow anaerobic sludge blanket (UASB) reactors are used to treat soft drink wastewater, offering high-volume loading capacity, optimal grain deposition, and the ability to bear impact loads. The use of support materials can enhance biological productivity and expedite the UASB start-up period. In this study, bone powder was utilized as a support material in a UASB reactor to remove contaminants from wastewater. During the 70-day sludge adaptation period, the treatment reactor achieved a 93% reduction in COD, while the control reactor achieved a 65% reduction. Biogas production was higher in the bone powder UASB reactor (1750 mL/d) compared to the control UASB reactor (1100 mL/d), and the bone powder UASB reactor demonstrated greater resistance to shock loading. The improvement in sludge settling, shear strength, and higher biological activity in the bone powder UASB reactor was attributed to the formation of large granular sludge. The size of the granular sludge increased further with the colonization of filamentous bacteria at the irregular levels of bone powder. [ABSTRACT FROM AUTHOR]

SUMMARY: Cyanobacteria are ancient organisms that contribute significantly to primary production in aquatic ecosystems. Although they are a group of microbes present in a wide range of environments, their diversity on anthropogenic substrates, namely microplastics, is still largely unknown. In the present study, we describe a new genus and species of cyanobacteria from the Nodosilineaceae family. Strains were isolated from foam microplastic particles obtained from beach sediments facing the Singapore Strait. This species is morphologically similar to the polyphyletic, cosmopolitan Leptolyngbya spp.; however, it forms an independent clade with 16S rRNA phylogeny and has a unique 16S–23S internal transcribed spacer secondary structure. To date, no cyanobacteria have been isolated and cultured from the surfaces of microplastic particles. Using a polyphasic approach combining morphological, phylogenetic and ecological traits, we describe a new genus and species Sphaerothrix gracilis. The presence of certain cyanobacteria rafting on microplastic surfaces can potentially indicate a long‐distance transport into new ecosystems with implications on toxicity and biodiversity. [ABSTRACT FROM AUTHOR]

The discovery of cable bacteria has revolutionized our understanding of long-distance biological electron transfer and has provoked the study of their distribution. Cable bacteria are widely distributed in aquatic environments and exhibit superior adaptations at the oxic–anoxic interface. The physiology and available genomes of cable bacteria have provided insights into the factors that control cable bacteria distribution, facilitating the anticipation of their occurrence and management of their ecological benefits. Cable bacteria create redox gradients, alter sediment geochemistry and nutrient cycling, influence microbial activity and networks, and alleviate multiple anthropogenic problems. The impact of cable bacteria can extend to the atmosphere, and their ecological significance may be more far-reaching than was previously believed. Cable bacteria have been identified and detected worldwide since their discovery in marine sediments in Aarhus Bay, Denmark. Their activity can account for the majority of oxygen consumption and sulfide depletion in sediments, and they induce sulfate accumulation, pH excursions, and the generation of electric fields. In addition, they can affect the fluxes of other elements such as calcium, iron, manganese, nitrogen, and phosphorous. Recent developments in our understanding of the impact of cable bacteria on element cycling have revealed their positive contributions to mitigating environmental problems, such as recovering self-purification capacity, enhancing petroleum hydrocarbon degradation, alleviating phosphorus eutrophication, delaying euxinia, and reducing methane emission. We highlight recent research outcomes on their distribution, state-of-the-art findings on their physiological characteristics, and ecological contributions. [ABSTRACT FROM AUTHOR]

While the immunodeficient status of NOD.Cg- Prkdc scid Il2rg tm1Wjl /SzJ (NSG) and NSG-related mice provides utility for numerous research models, it also results in increased susceptibility to opportunistic pathogens. Over a 9-week period, a high rate of mortality was reported in a housing room of NSG and NSG-related mice. Diagnostics were performed to determine the underlying etiopathogenesis. Mice submitted for evaluation included those found deceased (n = 2), cage mates of deceased mice with or without diarrhea (n = 17), and moribund mice (n = 8). Grossly, mice exhibited small intestinal and cecal dilation with abundant gas and/or digesta (n = 18), serosal hemorrhage and congestion (n = 6), or were grossly normal (n = 3). Histologically, there was erosive to ulcerative enterocolitis (n = 7) of the distal small and large intestine or widespread individual epithelial cell death with luminal sloughing (n = 13) and varying degrees of submucosal edema and mucosal hyperplasia. Cecal dysbiosis, a reduction in typical filamentous bacteria coupled with overgrowth of bacterial rods, was identified in 18 of 24 (75%) mice. Clostridium spp. and Paeniclostridium sordellii were identified in 13 of 23 (57%) and 7 of 23 (30%) mice, respectively. Clostridium perfringens (7 of 23, 30%) was isolated most frequently. Toxinotyping of C. perfringens positive mice (n = 2) identified C. perfringens type A. Luminal immunoreactivity to several clostridial species was identified within lesioned small intestine by immunohistochemistry. Clinicopathologic findings were thus associated with overgrowth of various clostridial species, though direct causality could not be ascribed. A diet shift preceding the mortality event may have contributed to loss of intestinal homeostasis. [ABSTRACT FROM AUTHOR]

The morphology is the consequence of evolution and adaptation. Escherichia coli is rod-shaped bacillus with regular dimension of about 1.5 μm long and 0.5 μm wide. Many shape-related genes have been identified and used in morphology engineering of this bacteria. However, little is known about if specific metabolism and metal irons could modulate bacteria morphology. Here in this study, we discovered filamentous shape change of E. coli cells overexpressing pigeon MagR, a putative magnetoreceptor and extremely conserved iron-sulfur protein. Comparative transcriptomic analysis strongly suggested that the iron metabolism change and iron accumulation due to the overproduction of MagR was the key to the morphological change. This model was further validated, and filamentous morphological change was also achieved by supplement E. coli cells with iron in culture medium or by increase the iron uptake genes such as entB and fepA. Our study extended our understanding of morphology regulation of bacteria, and may also serves as a prototype of morphology engineering by modulating the iron metabolism.

Type IV pili are filamentous appendages found in most bacteria and archaea, where they can support functions such as surface adhesion, DNA uptake, aggregation, and motility. In most bacteria, PilT-family ATPases disassemble adhesion pili, causing them to rapidly retract and produce twitching motility, important for surface colonization. As archaea do not possess PilT homologs, it was thought that archaeal pili cannot retract and that archaea do not exhibit twitching motility. Here, we use live-cell imaging, automated cell tracking, fluorescence imaging, and genetic manipulation to show that the hyperthermophilic archaeon Sulfolobus acidocaldarius exhibits twitching motility, driven by retractable adhesion (Aap) pili, under physiologically relevant conditions (75 °C, pH 2). Aap pili are thus capable of retraction in the absence of a PilT homolog, suggesting that the ancestral type IV pili in the last universal common ancestor (LUCA) were capable of retraction. Bacteria use filamentous appendages known as type IV pili for various functions, including twitching motility on surfaces. It was thought that archaeal pili cannot retract and that archaea do not exhibit twitching motility. However, Charles-Orszag et al. demonstrate that the model archaeon Sulfolobus acidocaldarius exhibits twitching motility, driven by retractable adhesion pili. [ABSTRACT FROM AUTHOR]

Filamentous cyanobacteria are one of the oldest and today still most abundant lifeforms on earth, with manifold implications in ecology and economics. Their flexible filaments, often several hundred cells long, exhibit gliding motility in contact with solid surfaces. The underlying force generating mechanism is not yet understood. Here, we demonstrate that propulsion forces and friction coefficients are strongly coupled in the gliding motility of filamentous cyanobacteria. We directly measure their bending moduli using micropipette force sensors, and quantify propulsion and friction forces by analyzing their self-buckling behavior, complemented with analytical theory and simulations. The results indicate that slime extrusion unlikely generates the gliding forces, but support adhesion-based hypotheses, similar to the better-studied single-celled myxobacteria. The critical self-buckling lengths align well with the peaks of natural length distributions, indicating the importance of self-buckling for the organization of their collective in natural and artificial settings. [ABSTRACT FROM AUTHOR]

This is the first report on abundance and diversity of cultured filamentous fungi and on abundance of yeasts in the sediments of the Laptev and East Siberian seas. A total of 63 isolates of filamentous fungi belonging to 32 morphotypes were obtained from 35 sediment samples. Most morphotypes were represented by single colonies in individual samples; the most frequently occurring species were Pseudeurotiumzonatum, Pseudogymnoascuspannorum, and Cordycepsfarinosа. In both seas, the abundance of filamentous fungi (up to 12 colonies per 1 g wet sediment) was lower than that of yeasts (up to 68 colonies per 1 g wet sediment). In the Laptev Sea, yeast abundance was low at all stations, while in the East Siberian Sea higher values were found at near-estuarine stations. [ABSTRACT FROM AUTHOR]

Introduction: Microplastics (MPs), identified as emerging contaminants, have been detected across diverse environmental media. Their enduring presence and small size facilitate the adsorption of organic pollutants and heavy metals, leading to combined pollution effects. MPs also accumulate in the food chain thus pose risks to animals, plants, and human health, garnering significant scholarly attention in recent years. Aerobic granular sludge (AGS) technology emerges as an innovative approach to wastewater treatment. However, the impacts of MPs on the operational efficiency and microbial characteristics of AGS systems has been insufficiently explored. Methods: This study investigated the effects of varying concentration (10, 50, and 100 mg/L) of biodegradable MPs (Polylactic Acid, PLA) and nonbiodegradable MPs (Polyethylene Terephthalate, PET) on the properties of AGS and explored the underlying mechanisms. Results and discussions: It was discovered that low and medium concentration of MPs (10 and 50 mg/L) showed no significant effects on COD removal by AGS, but high concentration (100 mg/L) of MPs markedly diminished the ability to remove COD of AGS, by blocking most of the nutrient transport channels of AGS. However, both PLA and PE promoted the nitrogen and phosphorus removal ability of AGS, and significantly increased the removal efficiency of total inorganic nitrogen (TIN) and total phosphorus (TP) at stages II and III (P < 0.05). High concentration of MPs inhibited the growth of sludge. PET noticeably deteriorate the sedimentation performance of AGS, while 50 mg/L PLA proved to be beneficial to sludge sedimentation at stage II. The addition of MPs promoted the abundance of Candidatus_Competibacter and Acinetobacter in AGS, thereby promoting the phosphorus removal capacity of AGS. Both 50 mg/L PET and 100 mg/L PLA caused large amount of white Thiothrix filamentous bacteria forming on the surface of AGS, leading to deterioration of the sludge settling performance and affecting the normal operation of the reactor. Comparing with PET, AGS proved to be more resistant to PLA, so more attention should be paid to the effect of non-biodegradable MPs on AGS in the future. [ABSTRACT FROM AUTHOR]

Cellulosimicrobium species (formerly known as Oerskovia) are Gram-positive filamentous bacteria in the family Promicromonosporaceae and are more commonly found in sewage and soil. The present study aimed to identify all the published cases of Cellulosimicrobium species infections in the literature, describe the epidemiological, clinical, and microbiological characteristics, and provide data regarding its antimicrobial resistance, treatment, and outcomes. A narrative review was performed based on a PubMed and Scopus database search. In total, 38 studies provided data on 40 patients with infections by these species. The median age of patients was 52.5 years, and 55% were male. The most common infection types were bacteremia, infective endocarditis (IE), osteoarticular infections, peritoneal dialysis-associated peritonitis, and endophthalmitis. Antimicrobial resistance to vancomycin and the combination of trimethoprim and sulfamethoxazole was minimal, and vancomycin was the most commonly used antimicrobial for treating these infections. Overall mortality was minimal for all infections, except for bacteremia and IE, which carried high mortality rates. [ABSTRACT FROM AUTHOR]

The ongoing global warming is likely to cause changes in the growth and species composition of aquatic epilithic communities. To be able to predict such changes, a field study was conducted in the cooling water discharge area of a nuclear power plant that releases brackish cooling water to the Baltic Sea at Forsmark. The power plant creates a temperature gradient in the field from 0 to ca. 8 °C above normal temperature. The project was concentrated on the growth and distribution of four dominant taxa in the upper littoral zone: the colonial cyanobacterium Rivularia atra and the three filamentous macroalgae Cladophora glomerata (green), Ulva spp. (green) and Ceramium tenuicorne (red). Overall, Cladophora increased strongly, Ulva spp. increased slightly and Ceramium decreased strongly in abundance with higher water temperature. For Rivularia these results were corroborated in a laboratory experiment and studied in more detail. The colonies collected at 18 °C in the field were experimentally exposed to 18 °C, 22 °C and 26 °C in climate chambers for 50 days. Growth rates were highest in 18 °C and lowest in 22 and 26 °C. Addition of extra stress in the form of a heavy metal (copper) decreased growth in all temperatures, but highest growth rates still occurred in 18 °C. Rivularia was less stressed in 18 °C than in 22 °C and 26 °C, which was shown by, higher chlorophyll a (chla) concentration, higher photosynthetic performance (measured as electron transport rate by pulse amplitude modulated fluorescence), lower zeaxanthin concentration and a lower carotenoids:chla ratio. [ABSTRACT FROM AUTHOR]

The VITEK MS PRIME (bioMérieux, Marcy-l'Étoile, France), a newly developed matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) system, alongside the VITEK PICKME pen (PICKME), offers easy sample preparation for bacteria and yeasts. The VITEK MS PRIME also offers two software platforms for filamentous fungi: the IVD database and the RUO database. Our study evaluated its identification agreement on 320 clinical isolates of bacteria and yeasts, comparing PICKME and traditional wooden toothpick sampling techniques against MicroIDSys Elite (ASTA) results. Additionally, we assessed the IVD (v3.2) and SARAMIS (v4.16) RUO databases on 289 filamentous fungi against molecular sequencing. The concordance rates for species-level identification of bacteria and yeasts were about 89.4% (286/320) between the PICKME and wooden toothpick, and about 83.4–85.3% between the VITEK MS PRIME and ASTA MicroIDSys Elite. Retesting with PICKME improved concordance to 91.9%. For filamentous fungi, species-level identification reached 71.3% with the IVD database and 85.8% with RUO, which significantly enhanced basidiomycetes' identification from 35.3% to 100%. Some strains in the IVD database, like Aspergillus versicolor, Exophiala xenobiotica, and Nannizzia gypsea, failed to be identified. The VITEK MS PRIME with PICKME offers reliable and efficient microorganism identification. For filamentous fungi, combined use of the RUO database can be beneficial, especially for basidiomycetes. [ABSTRACT FROM AUTHOR]

A novel endophytic actinomycete, strain MEP2-6T, was isolated from scab tissues of potato tubers collected from Mae Fag Mai Sub-district, San Sai District, Chiang Mai Province, Thailand. Strain MEP2-6T is a gram-positive filamentous bacteria characterized by meso-diaminopimelic acid in cell wall peptidoglycan and arabinose, galactose, glucose, and ribose in whole-cell hydrolysates. Diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, and hydroxy-phosphatidylethanolamine were the major phospholipids, of which MK-9(H6) was the predominant menaquinone, whereas iso-C16:0 and iso-C15:0 were the major cellular fatty acids. The genome of the strain was 10,277,369 bp in size with a G + C content of 71.7%. The 16S rRNA gene phylogenetic and core phylogenomic analyses revealed that strain MEP2-6T was closely related to Amycolatopsis lexingtonensis NRRL B-24131T (99.4%), A. pretoriensis DSM 44654T (99.3%), and A. eburnea GLM-1T (98.9%). Notably, strain MEP2-6T displayed 91.7%, 91.8%, and 87% ANIb and 49%, 48.8%, and 35.4% dDDH to A. lexingtonensis DSM 44653T (=NRRL B-24131T), A. eburnea GLM-1T, and A. pretoriensis DSM 44654T, respectively. Based on phenotypic, chemotaxonomic, and genomic data, strain MEP2-6T could be officially assigned to a novel species within the genus Amycolatopsis, for which the name Amycolatopsis solani sp. nov. has been proposed. The type of strain is MEP2-6T (=JCM 36309T = TBRC 17632T = NBRC 116395T). Amycolatopsis solani MEP2-6T was strongly proven to be a non-phytopathogen of potato scab disease because stunting of seedlings and necrotic lesions on potato tuber slices were not observed, and there were no core biosynthetic genes associated with the BGCs of phytotoxin-inducing scab lesions. Furthermore, comparative genomics can provide a better understanding of the genetic mechanisms that enable A. solani MEP2-6T to adapt to the plant endosphere. Importantly, the strain smBGCs accommodated 33 smBGCs encoded for several bioactive compounds, which could be beneficially applied in the fields of agriculture and medicine. Consequently, strain MEP2-6T is a promising candidate as a novel biocontrol agent and antibiotic producer. [ABSTRACT FROM AUTHOR]

Root-knot nematodes (RKN) are one of the most harmful soil-borne plant pathogens in the world. Actinobacteria are known phytopathogen control agents. The aim of this study was to select soil actinobacteria with control potential against the RKN (Meloidogyne javanica) in tomato plants and to determine mechanisms of action. Ten isolates were tested and a significant reduction was observed in the number of M. javanica eggs, and galls 46 days after infestation with the nematode. The results could be explained by the combination of different mechanisms including parasitism and induction of plant defense response. The M. javanica eggs were parasited by all isolates tested. Some isolates reduced the penetration of juveniles into the roots. Other isolates using the split-root method were able to induce systemic defenses in tomato plants. The 4L isolate was selected for analysis of the expression of the plant defense genes TomLoxA, ACCO, PR1, and RBOH1. In plants treated with 4L isolate and M. javanica, there was a significant increase in the number of TomLoxA and ACCO gene transcripts. In plants treated only with M. javanica, only the expression of the RBOH1 and PR1 genes was induced in the first hours after infection. The isolates were identified using 16S rRNA gene sequencing as Streptomyces sp. (1A, 3F, 4L, 6O, 8S, 9T, and 10U), Kribbella sp. (5N), Kitasatospora sp. (2AE), and Lentzea sp. (7P). The efficacy of isolates from the Kitasatospora, Kribbella, and Lentzea genera was reported for the first time, and the efficacy of Streptomyces genus isolates for controlling M. javanica was confirmed. All the isolates tested in this study were efficient against RKN. This study provides the opportunity to investigate bacterial genera that have not yet been explored in the control of M. javanica in tomatoes and other crops. [ABSTRACT FROM AUTHOR]

Sludge bulking caused by filamentous bacteria is a prevalent issue in wastewater treatment systems. While previous studies have primarily concentrated on controlling sludge bulking, the biological risks associated with it have been overlooked. This study demonstrates that excessive growth of filamentous bacteria during sludge bulking can significantly increase the abundance of antibiotic resistance genes (ARGs) in activated sludge. Through metagenomic analysis, we identified specific ARGs carried by filamentous bacteria, such as Sphaerotilus and Thiothrix, which are responsible for bulking. Additionally, by examining over 1,000 filamentous bacterial genomes, we discovered a diverse array of ARGs across different filamentous bacteria derived from wastewater treatment systems. Our findings indicate that 74.84% of the filamentous bacteria harbor at least one ARG, with the occurrence frequency of ARGs in these bacteria being approximately 1.5 times higher than that in the overall bacterial population in activated sludge. Furthermore, genomic and metagenomic analyses have shown that the ARGs in filamentous bacteria are closely linked to mobile genetic elements and are frequently found in potentially pathogenic bacteria, highlighting potential risks posed by these filamentous bacteria. These insights enhance our understanding of ARGs in activated sludge and underscore the importance of risk management in wastewater treatment systems.

The Eikelboom filamentous bacterial morphotype ‘Haliscomenobacter hydrossis Eis ubiquitous in Japanese and other wastewater treatment plants (WWTPs). However, it is still largely ‘identified Emicroscopically on its distinctive morphology, and only one species Haliscomenobacter hydrossis is recognized currently. Thus, little is known about the true level of phylogenetic diversity among members of this morphotype. Here, using 16S rRNA gene amplicon data we reveal that populations of this morphotype belong to several clades. Fluorescence in situ hybridization (FISH) probes were designed against members of each of these morphotypes, together with a new probe more specific than those currently available to target members of the genus Haliscomenobacter. Japanese municipal WWTPs were surveyed to evaluate the abundances of ‘H. hydrossis Emorphotype using FISH analysis with the existing and newly designed FISH probes. Data showed that some ‘H. hydrossis Emorphotypes appeared to show suppressed growth in biological nitrogen removal processes, although process configuration seemed not to be a critical factor in determining their abundances. Their excessive growth appears to cause activated bulking incidents in WWTPs. These data may assist in extending our currently poor understanding of ‘H. hydrossis Ephylogeny and systematics and provide tools to study its global distribution.

The genus Dendroctonus is a Holarctic taxon composed of 21 nominal species; some of these species are well known in the world as disturbance agents of forest ecosystems. Under the bark of the host tree, these insects are involved in complex and dynamic associations with phoretic ectosymbiotic and endosymbiotic communities. Unlike filamentous fungi and bacteria, the ecological role of yeasts in the bark beetle holobiont is poorly understood, though yeasts were the first group to be recorded as microbial symbionts of these beetles. Our aim was characterize and compare the gut fungal assemblages associated to 14 species of Dendroctonus using the internal transcribed spacer 2 (ITS2) region. A total of 615,542 sequences were recovered yielding 248 fungal amplicon sequence variants (ASVs). The fungal diversity was represented by 4 phyla, 16 classes, 34 orders, 54 families, and 71 genera with different relative abundances among Dendroctonus species. The α-diversity consisted of 32 genera of yeasts and 39 genera of filamentous fungi. An analysis of β-diversity indicated differences in the composition of the gut fungal assemblages among bark beetle species, with differences in species and phylogenetic diversity. A common core mycobiome was recognized at the genus level, integrated mainly by Candida present in all bark beetles, Nakazawaea, Cladosporium, Ogataea, and Yamadazyma. The bipartite networks confirmed that these fungal genera showed a strong association between beetle species and dominant fungi, which are key to maintaining the structure and stability of the fungal community. The functional variation in the trophic structure was identified among libraries and species, with pathotroph-saprotroph-symbiotroph represented at the highest frequency, followed by saprotroph-symbiotroph, and saprotroph only. The overall network suggested that yeast and fungal ASVs in the gut of these beetles showed positive and negative associations among them. This study outlines a mycobiome associated with Dendroctonus nutrition and provides a starting point for future in vitro and omics approaches addressing potential ecological functions and interactions among fungal assemblages and beetle hosts. [ABSTRACT FROM AUTHOR]

There are many fields where it is of interest to measure the elastic moduli of tiny fragile fibers, such as filamentous bacteria, actin filaments, DNA, carbon nanotubes, and functional microfibers. The elastic modulus is typically deduced from a sophisticated tensile test under a microscope, but the throughput is low and limited by the timeconsuming and skill-intensive sample loading/unloading. Here, we demonstrate a simple microfluidic method enabling the high-throughput measurement of the elastic moduli of microfibers by rope coiling using a localized compression, where sample loading/unloading are not needed between consecutive measurements. The rope coiling phenomenon occurs spontaneously when a microfiber flows from a small channel into a wide channel. The elastic modulus is determined by measuring either the buckling length or the coiling radius. The throughput of this method, currently 3,300 fibers per hour, is a thousand times higher than that of a tensile tester. We demonstrate the feasibility of the method by testing a nonuniform fiber with axially varying elastic modulus. We also demonstrate its capability for in situ inline measurement in a microfluidic production line. We envisage that high-throughput measurements may facilitate potential applications such as screening or sorting by mechanical properties and real-time control during production of microfibers. [ABSTRACT FROM AUTHOR]

Actinomycetes are the potential producers of secondary metabolites of vivid applications; they are isolated from almost all the sources both terrestrial and aquatic habitats. Actinomycetes are a group of Gram-positive bacteria known for their filamentous structure and ability to produce a diverse array of bioactive compounds. These bioactive compounds include antibiotics, antifungals, antivirals, anticancer agents, immunosuppressants, and enzymes. Actinomycetes have been a major source of these bioactive compounds and have played a significant role in the development of many therapeutic drugs. Actinomycetes, which are isolated from practically all sources in both terrestrial and aquatic ecosystems, have the potential to create secondary metabolites with diverse uses. A class of Grampositive bacteria called actinomycetes is distinguished by its filamentous structure and capacity to manufacture a wide range of bioactive substances. Antibiotics, antifungals, antivirals, cancer preventatives, immunosuppressants, and enzymes are a few examples of these bioactive substances. These bioactive substances have primarily come from actinomycetes, which have also contributed significantly to the creation of several medicinal medications. However, actinomycetes isolation and cultivation can be challenging due to their slow growth rate and complex nutritional requirements. In order to isolate and cultivate actinomycetes, several pre-treatment methods and media can be employed. [ABSTRACT FROM AUTHOR]

During the study of diversity in filamentous cyanobacteria in China, two strains (WZU0719 and WZU0723) with the form of thin filaments were isolated from the surface of Qiandao Lake, a large freshwater lake in Zhejiang Province, China. A comprehensive analysis was conducted, incorporating morphological, ecological, and molecular data. The morphological examination provided an initial identification as a Leptolyngbya-like cyanobacterium. Genetic characterization was also performed by amplifying the 16S rRNA gene and the 16S-23S rRNA internal transcribed spacer (ITS) region. The phylogenetic grouping based on the 16S rRNA gene demonstrates that the examined strain is unequivocally assigned to the Pegethrix genus. However, it possesses distinct phylogenetic divergence from the six described Pegethrix species. Additionally, discrepancies in habitat further differentiate it from other members of this genus. Employing the polyphasic approach, we present a comprehensive account of the newly discovered taxa: Pegethrix qiandaoensis sp. nov. The novel taxonomic finding in this research significantly contributes to enhancing the comprehension of Pegethrix diversity across various habitats. [ABSTRACT FROM AUTHOR]

The velocity of the gliding movement of filamentous cyanobacteria on a solid surface usually has a strong temperature dependency, and the higher the temperature, the faster the speed. Former studies on this phenomenon were conducted using filamentous cyanobacteria with straight morphology. We examined the velocity of the gliding movement of Arthrospira platensis NIES-39 along its longitudinal axis to see if the same was true for this cyanobacterium with helicoid trichomes. Experimental results showed little temperature dependency in the velocity in a wide temperature range in this cyanobacterium. However, when we examined the velocity using mutants with straight trichomes, their velocity was strongly affected by temperature, like other formerly analyzed filamentous cyanobacteria. This result indicates that the helicoid morphology of A. platensis trichomes confers temperature compensation to their migration velocity, enabling them to keep a relatively constant velocity under various temperatures. Migration of wild-type trichomes is considerably suppressed compared to the straight-trichome mutants on solid media. The temperature compensation in the locomotion of this organism appears to be established as part of such a suppression. It was also found that the velocity of this cyanobacterium depended on the trichome length when they were atypically short (<250 µm); the shorter the trichomes, the slower the gliding movement tended to be. This result indicates that the coordinated action of a high number of cells constituting the trichome is required for efficient gliding movement. [ABSTRACT FROM AUTHOR]

This article explores the research of Andrea Ling, who focuses on the intersection of design, fabrication, and biology. Ling's work involves using biological and computational processes to create regenerative systems of production. The article highlights three specific projects that involve the intentional decay of biologically derived materials, such as plant-based paints, enzymes, bacteria, and fungi, to create new objects. Ling's goal is to explore the potential of decay as a fabrication process and to incorporate mechanisms of constructive renewal into the objects we create. The article discusses the challenges and benefits of working with biological matter in artistic and design projects, emphasizing the need to consider the aesthetic, sensorial, and programmatic aspects of decay. It also explores the concept of decay as a natural and necessary process and the potential for incorporating decay into human-made projects to promote resilience and renewal. The article references specific projects, including one that used rotting tree stumps as a stage set for performance art. Overall, the article encourages a reevaluation of our relationship with decay and the integration of decay into design processes. [Extracted from the article]

Microbial communities are found in all habitable environments and often occur in assemblages with self-organized spatial structures developing over time. This complexity can only be understood, predicted, and managed by combining experiments with mathematical modeling. Individual-based models are particularly suited if individual heterogeneity, local interactions, and adaptive behavior are of interest. Here we present the completely overhauled software platform, the individual-based Dynamics of Microbial Communities Simulator, iDynoMiCS 2.0, which enables researchers to specify a range of different models without having to program. Key new features and improvements are: (1) Substantially enhanced ease of use (graphical user interface, editor for model specification, unit conversions, data analysis and visualization and more). (2) Increased performance and scalability enabling simulations of up to 10 million agents in 3D biofilms. (3) Kinetics can be specified with any arithmetic function. (4) Agent properties can be assembled from orthogonal modules for pick and mix flexibility. (5) Force-based mechanical interaction framework enabling attractive forces and non-spherical agent morphologies as an alternative to the shoving algorithm. The new iDynoMiCS 2.0 has undergone intensive testing, from unit tests to a suite of increasingly complex numerical tests and the standard Benchmark 3 based on nitrifying biofilms. A second test case was based on the "biofilms promote altruism" study previously implemented in BacSim because competition outcomes are highly sensitive to the developing spatial structures due to positive feedback between cooperative individuals. We extended this case study by adding morphology to find that (i) filamentous bacteria outcompete spherical bacteria regardless of growth strategy and (ii) non-cooperating filaments outcompete cooperating filaments because filaments can escape the stronger competition between themselves. In conclusion, the new substantially improved iDynoMiCS 2.0 joins a growing number of platforms for individual-based modeling of microbial communities with specific advantages and disadvantages that we discuss, giving users a wider choice. Author summary: Microbes are fascinating in their own right and play a tremendously important role in ecosystems. They often form complex, self-organized communities with spatial heterogeneity that is changing over time. Such complexity is challenging to understand and manage without the help of mathematical models. Individual-based models are one type of mathematical model that is particularly suited if differences between individual microbes, local interactions and adaptive behavior are important. We have developed a completely overhauled version of iDynoMiCS, a software that allows users to develop, run and analyze a wide range of individual-based models without having to program the software themselves. There are several capability enhancements and numerous small improvements, for example the ability to model different shapes of cells combined with physically realistic mechanical interactions between neighboring cells. We showcase this by simulating the competition between filaments, long chains of cells, with single cells and find that filaments outcompete single cells as they can spread quickly to new territory with higher levels of resources. Users now have a wider choice of platforms so we provide guidance on which platform might be most suitable for a given purpose. [ABSTRACT FROM AUTHOR]

Hard-shelled foraminifera are protists able to build a calcareous or agglutinated shell (called a "test"). Here we study the impact of sediment acidification on calcareous test preservation. For this study, sediment cores were sampled in the macrotidal Auray estuary located on the French Atlantic coast. Living and dead foraminifera were quantified until 5 cm depth and discriminated using the Cell-Tracker™ Green vital marker. The pH and oxygen profiles combined with quantitative polymerase chain reaction (qPCR) suggested that cable bacteria were most likely to cause the acidifying process. Cable bacteria (CB) are filamentous bacteria coupling sulfide oxidation to oxygen reduction over centimetre distances, generating a strong pH gradient within the first few centimetres of the sediment that could affect the microhabitats occupied by benthic foraminifera. On two different intertidal mudflats, volumetric filament densities have been estimated. They were comparable to those observed in the literature for coastal environments, with 7.4 ± 0.4 and 74.4 ± 5.0 m cm -3 per bulk sediment, respectively. Highly contrasting sediment acidification (from low to very intense) was described from 1.0 to 2.4 Δ pH. This seems to lead to various dissolution stages of the foraminiferal calcareous test from intact to fully dissolved tests revealing the organic lining. The dissolution scale is based on observations of living Ammonia spp. and Haynesina germanica specimens under a scanning electronic microscope. Furthermore, dead foraminiferal assemblages showed a strong calcareous test loss and an organic lining accumulation throughout depth under low pH, hampering the test preservation in deep sediment. These changes in both living and dead foraminiferal assemblages suggest that cable bacteria must be considered in ecological monitoring and historical studies using foraminifera as bioindicators and paleoenvironmental proxies. [ABSTRACT FROM AUTHOR]

In their natural environment, fungi are subjected to a wide variety of environmental stresses which they must cope with by constantly adapting the architecture of their growing network. In this work, our objective was to finely characterize the thallus development of the filamentous fungus Podospora anserina subjected to different constraints that are simple to implement in vitro and that can be considered as relevant environmental stresses, such as a nutrient-poor environment or non-optimal temperatures. At the Petri dish scale, the observations showed that the fungal thallus is differentially affected (thallus diameter, mycelium aspect) according to the stresses but these observations remain qualitative. At the hyphal scale, we showed that the extraction of the usual quantities (i.e. apex, node, length) does not allow to distinguish the different thallus under stress, these quantities being globally affected by the application of a stress in comparison with a thallus having grown under optimal conditions. Thanks to an original geomatics-based approach based on the use of automatized Geographic Information System (GIS) tools, we were able to produce maps and metrics characterizing the growth dynamics of the networks and then to highlight some very different dynamics of network densification according to the applied stresses. The fungal thallus is then considered as a map and we are no longer interested in the quantity of material (hyphae) produced but in the empty spaces between the hyphae, the intra-thallus surfaces. This study contributes to a better understanding of how filamentous fungi adapt the growth and densification of their network to potentially adverse environmental changes. [ABSTRACT FROM AUTHOR]

Background: Biofilms in sulfide-rich springs present intricate microbial communities that play pivotal roles in biogeochemical cycling. We studied chemoautotrophically based biofilms that host diverse CPR bacteria and grow in sulfide-rich springs to investigate microbial controls on biogeochemical cycling. Results: Sulfide springs biofilms were investigated using bulk geochemical analysis, genome-resolved metagenomics, and scanning transmission X-ray microscopy (STXM) at room temperature and 87 K. Chemolithotrophic sulfur-oxidizing bacteria, including Thiothrix and Beggiatoa, dominate the biofilms, which also contain CPR Gracilibacteria, Absconditabacteria, Saccharibacteria, Peregrinibacteria, Berkelbacteria, Microgenomates, and Parcubacteria. STXM imaging revealed ultra-small cells near the surfaces of filamentous bacteria that may be CPR bacterial episymbionts. STXM and NEXAFS spectroscopy at carbon K and sulfur L2,3 edges show that filamentous bacteria contain protein-encapsulated spherical elemental sulfur granules, indicating that they are sulfur oxidizers, likely Thiothrix. Berkelbacteria and Moranbacteria in the same biofilm sample are predicted to have a novel electron bifurcating group 3b [NiFe]-hydrogenase, putatively a sulfhydrogenase, potentially linked to sulfur metabolism via redox cofactors. This complex could potentially contribute to symbioses, for example, with sulfur-oxidizing bacteria such as Thiothrix that is based on cryptic sulfur cycling. One Doudnabacteria genome encodes adjacent sulfur dioxygenase and rhodanese genes that may convert thiosulfate to sulfite. We find similar conserved genomic architecture associated with CPR bacteria from other sulfur-rich subsurface ecosystems. Conclusions: Our combined metagenomic, geochemical, spectromicroscopic, and structural bioinformatics analyses of biofilms growing in sulfide-rich springs revealed consortia that contain CPR bacteria and sulfur-oxidizing Proteobacteria, including Thiothrix, and bacteria from a new family within Beggiatoales. We infer roles for CPR bacteria in sulfur and hydrogen cycling. 8FE2mu4H1cxgQVBqjGxsC2 Video Abstract [ABSTRACT FROM AUTHOR]

The discharge of industrial water requires the removal of its pollutants, where biological wastewater treatment plants (WWTPs) are the most used systems. Biological WWTPs make use of activated sludge (AS), where bacteria are responsible for the removal of pollutants. However, our knowledge of the microbial communities of industrial plants is limited. Understanding the microbial population is essential to provide solutions to industrial problems such as bulking. The aim of this study was to identify at a high taxonomic resolution the bacterial population of 29 industrial WWTPs using 16S rRNA amplicon sequencing. Our results revealed that the main functional groups were dominated by Thauera and Zoogloea within denitrifiers, Dechloromonas in phosphate-accumulating organisms, and Defluviicoccus in glycogen-accumulating organisms. The activated sludge characterization indicated that 59% of the industrial plants suffered from bulking sludge, with DSVI values of up to 448 mL g−1. From the bulking cases, 72% corresponded to filamentous bulking with Thiothrix as the most abundant filament; meanwhile, the other 28% corresponded to viscous bulking sludge in which Zoogloea was the most abundant genus. Furthermore, the bacterial population did not share a core of taxa across all industrial plants. However, 20 genera were present in at least 50% of the plants comprising the general core, including Thauera, Ca. Competibacter, and several undescribed microorganisms. Moreover, statistical analysis revealed that wastewater salinity strongly affected the microbial richness of the industrial plants. The bacterial population across industrial plants differed considerably from each other, resulting in unique microbial communities that are attributed to the specificity of their wastewaters. Key points: • The general core taxa of industrial plants were mostly made up of undescribed bacterial genera. • Filamentous bacteria constituted on average 4.1% read abundance of the industrial WWTPs. • Viscous bulking remains a significant type of bulking within industrial WWTPs. [ABSTRACT FROM AUTHOR]

Although South Africa is known as one of the most biodiverse countries in the world, based on its unique plants and animals, microorganisms have received much less attention. Microorganisms in general and actinobacteria in particular are an underexplored source of new medicines. Recent studies have demonstrated the presence of diverse cultivable actinobacteria from various biomes. However, investigations of the natural product diversity associated with these microorganisms are lacking. We hereby present a review of natural products isolated from South African actinobacteria together with their biological activities. Many of these natural products are structurally novel and include compounds belonging to the following classes: anthraquinones, isoflavonoids, ketolides, macrolides, macrolactams, tripeptides and depsipeptides. They show a wide range of biological activities including antibacterial, antifungal, cytotoxic and antitumour activities. Significance: * This review highlights the importance of actinobacteria in the discovery of new medicines and summarises the state-of-the-art on their research in South Africa. * We reveal a gap in the exploitation of this resource and emphasise the opportunities for multidisciplinary research. [ABSTRACT FROM AUTHOR]

Frutexites‐like microstructures are described from the exhumed Late Devonian reef complexes of the northern Canning Basin, Western Australia. Several high‐resolution imaging techniques, including X‐ray microcomputerised tomography, scanning electron microscopy and X‐ray fluorescence microscopy, were used to investigate morphology and composition in two samples. Three types of Frutexites‐like microstructures (Types I–III) have been identified. Type I, found lining an early marine cement‐filled cavity in fore‐reef grainstone facies, consists of dendritic structures formed primarily of coccoid bacteria with filamentous bacteria embedded in sheets of amorphous extracellular polymeric substances (EPS). These ferromanganiferous dendrites have laminated to spheroidal textures. Types II and III are from a toe‐of‐slope hardground. Type II grew in a crypt between two corals, is also dendritic and composed of bacilliform and filamentous bacteria embedded in an amorphous EPS sheet. The opaqueness of these ferriferous dendrites precludes more detailed description of textures. Type III grew as branching columnar microstromatolites and is composed of entwined filaments of Girvanella, Rothpletzella and Wetheredella with Fe‐enriched outer walls that generate Frutexites‐like microstructures. Types I and II resemble Frutexites sensu stricto as defined by Maslov (Stromatolites, Trudy Instituta geologicheskikh nauk Akademiya nauk SSR, 1960) and are the result of the consecutive growth and permineralisation of biofilms composed of mixed bacterial communities growing in cryptic habitats. Type III superficially resembles Frutexites sensu stricto based on macroscopic field observations, however, detailed microscopic analysis reveals that it is composed of Fe‐enriched tubular walls surrounded by Mn‐enriched calcite. [ABSTRACT FROM AUTHOR]

Contextualization: Hydrolases are some of the most used enzymes in different industrial processes and can be obtained from microorganisms such as bacteria and fungi. Filamentous bacteria are a group of microorganisms present in various environments, and many of these species produce extracellular hydrolases catalyzing the decomposition of compounds such as proteins and polysaccharides. The most representative genus is Streptomyces, a bacterial group found in most soils. It synthesizes enzymes of interest and main antibiotics of microbial origin. Knowledge gap: The high soil diversity in the country is an opportunity for the bioprospecting of native microorganisms with enzymatic potential, which can be found in different understudied agroecosystems and their biochemical capacities could be associated with the environmental and nutritional conditions of the sites where they are found. Objective: To verify the presence of filamentous bacteria producers of hydrolytic enzymes with potential industrial application in different soil types and a composting system. Methodology: Samples were taken from a composting system, from the floor of a path in a native forest, from the rhizospheres of a live fence, and hydrangeas, avocado, blackberry, and Cole crops. Filamentous bacteria were isolated based on the colonies with the corresponding morphology. Enzyme activities were determined using the disk diffusion method to quantify the halos of hydrolysis in starch, carboxymethyl cellulose, gelatin, and olive oil mediums. Results and conclusions: 43 isolates of filamentous bacteria were obtained, of which 36, 42, 39, and 30 had amylase, cellulase, gelatinase, and lipase activity, respectively. At least one isolated with some hydrolytic activity was found in all samples. The composting system and the rhizosphere of the live fence were the sites from which more bacterial isolates were obtained with higher activity. It is likely related to characteristics such as humidity and organic matter from the soils from which they were recovered. [ABSTRACT FROM AUTHOR]

ε-Poly-L-lysine (ε-PL) is a natural and safe food preservative mainly produced by the aerobic, filamentous bacterium Streptomyces albulus. Therefore, it is crucial to breed superior ε-PL-producing strains to enhance fermentation efficiency to reduce production costs. Metabolic engineering is an effective measure for strain modification, but there are few reports on key genes for ε-PL biosynthesis. In this study, metabolic flux analysis was employed to identify potential key genes in ε-PL biosynthesis in S. albulus WG-608. A total of six potential key genes were identified. Three effective key genes (ppc, pyc and pls) were identified for the first time in ε-PL biosynthesis through overexpression experiments. It also presents the first demonstration of the promoting effects of ppc and pyc on ε-PL biosynthesis. Three genes were then co-expressed in S. albulus WG-608 to obtain OE-ppc-pyc-pls, which exhibited an 11.4% increase in ε-PL production compared to S. albulus WG-608, with a 25.5% increase in specific ε-PL production. Finally, the metabolic flux analysis of OE-ppc-pyc-pls compared to S. albulus WG-608 demonstrated that OE-ppc-pyc-pls successfully altered the metabolic flux as expected. This study not only provides a theoretical basis for the metabolic engineering of ε-PL-producing strains but also provides an effective approach for the metabolic engineering of other metabolites. [ABSTRACT FROM AUTHOR]

This document is a summary of articles published in the journal Applied & Environmental Microbiology. The articles cover a range of topics, including the ecophysiology of sulfate-reducing bacteria, the use of a fungal cutinase for plastic degradation, a new putative depolymerase that degrades the capsule of Klebsiella pneumoniae, a genetic toolkit to study archaeal viruses, the synthesis of cellulose by Streptomycetes, and the transport of bacteria by soil protists along plant roots. These articles provide valuable insights into various aspects of microbiology and offer opportunities for further research in these areas. [Extracted from the article]

Cable bacteria are unique multicellular organisms that live in the sediment at the bottom of oceans and lakes. They form long chains called filaments, with each filament consisting of thousands of cells connected together. What sets cable bacteria apart is their ability to generate energy through electrical teamwork. The cells within a filament work together to transfer electrons from hydrogen sulfide to oxygen, generating electricity in the process. This unique energy generation allows cable bacteria to thrive in environments where resources are spatially separated. Further research is needed to understand the mechanisms behind this electrical cooperation and its implications. [Extracted from the article]

Aerobic Granular Sludge (AGS) technology received special attention among wastewater researchers due to the compact system and simultaneous organics and nutrient removal in one single unit reactor, especially for domestic wastewater treatment. However, it is reported in the studies that the stability of AGS formation depending on organic loading rate (OLR). A low organic loading rate led to the problem of occurrence of the filamentous bacteria in the system, which disturbed the stability of compact granules formation. Therefore, researchers intended to further investigate this bottleneck of the AGS technology. This study aims to cultivate aerobic granular sludge in actual domestic wastewater at organic loading rate of 1.6 kg COD per day and COD/N/P ratio was 200/25/10. The experiment was carried out in a 2.5 L working volume of column reactor that operated with 3 h of sequencing batch reactor (SBR) cycle time for 29 days. This AGS system achieved reliability results in the treatment of domestic wastewater with a good average removal rate for COD, around 80 %. For Ammoniacal Nitrogen (AMN) and Total Phosphorus (TP), AGS system successfully treat up to the maximum of 88.6 and 71.7 %. Meanwhile, AGS size >1.0 mm was successfully cultivated with an average settling velocity of 40 m/h and 30 min Sludge Volume Index (SVI) of 60 mL/g. [ABSTRACT FROM AUTHOR]

Simple filamentous cyanobacteria comprise a diverse and polyphyletic group of species, primarily in the orders Leptolyngbyales and Oscillatoriales, that need more sampling to improve their taxonomy. Oceanic islands, such as the Azores archipelago, present unique habitats and biogeographic conditions that harbor an unknown range of diversity of microorganisms. Filamentous cyanobacteria isolated from aquatic habitats in the Azores and maintained in the BACA culture collection were described using morphology, both light and transmission electron microscopy, ecology, and genetic data of the 16S rRNA gene sequences and 16S–23S Internal Transcribed Spacer (ITS) rRNA region secondary structure. Our analyses revealed two new monophyletic genera: Tumidithrix elongata gen. sp. nov. (Pseudanabaenaceae) and Radiculonema aquaticum gen. sp. nov. (Leptolyngbyaceae). In addition, two new species Leptodesmis lacustris sp. nov. (Leptolyngbyaceae) and Pycnacronema lacustrum sp. nov. (Wilmottiaceae) are reported as the first aquatic species for these genera. The description of these new taxa and the genetic study of an isolate of Leptodesmis alaskaensis from the Azores followed the polyphasic approach, identifying diacritical features. Our results reinforce the need for taxonomic studies on cyanobacteria from less‐studied habits and geographic regions, which have a potential for new taxa description. [ABSTRACT FROM AUTHOR]

Novel CRISPR systems capable of cleaving both DNA and RNA are progressively emerging as attractive tools for genome manipulation of prokaryotic and eukaryotic organisms. We report specific characteristics of CRISPR systems present in Oxynema aestuarii AP17, a halotolerant, filamentous cyanobacterium and the second known member of the Oxynema genus. In‐silico analyses of its whole‐genome sequence revealed the presence of multiple Type I and Type III CRISPR loci with one Type I‐G system previously unreported in cyanobacteria. We further identified the leader sequences at the 5′ end of multiple CRISPR loci, many of which were distinct from previously reported cyanobacterial CRISPR leaders. Phylogenetic analyses of the O. aestuarii AP17 Cas1 proteins revealed two protein sequences that were unique and distantly related to other cyanobacterial Cas1 protein sequences. Our findings are significant because novel Class 1 CRISPR systems possess multi‐subunit effectors and are highly flexible for repurposing by protein domain fusions made to the effector complex. Additionally, Type III CRISPRs are particularly useful for genome editing in certain extremophiles for which mesophilic Type II CRISPRs are ineffective. [ABSTRACT FROM AUTHOR]

By summarizing the existing literature, the filamentous bacteria detected in the different countries and regions are similar, which mainly include Ca. M. parvicella, Thiothrix, H. hydrossis, Ca. Amarolin- ea. Many factors such as nutrients, temperature, pH, dissolved oxygen content, and sludge load could affect the growth of filamentous bacteria severely. Although the overgrowth of filamentous bacteria can be inhibi- ted by adjusting the operating parameters or adding chemicals, such common methods have some limitations. Combined with the current status of research, new methods based on quorum sensing and quorum quenching are also introduced. [ABSTRACT FROM AUTHOR]

Streptomyces are very important Gram-positive filamentous bacteria because they can produce many beneficial secondary metabolites with various biological activities. The study aims to isolate and identify novel Streptomyces strains from terrestrial habitats in the United Arab Emirates (UAE) with antimicrobial and cytotoxic properties. The antimicrobial efficacy was assessed using the disk and well susceptibility methods. Crude ethyl acetate extracts of active-producing strains were used to determine the antimicrobial activity by minimum inhibitory concentration (MIC) against E. coli, S. aureus, C. albicans, S. cerevisiae, B. subtilis, and E. coli-ESBL (extended-spectrum Beta-Lactamase), and cytotoxic properties against HeLa cells by MTT assay and DAPI staining. The novelty of the strains was determined by sequencing the 16S rRNA fragment. Results showed that antimicrobial activity was observed for CSK1, CSK3, CSW2, CSU1, CSU2, and CSG1 strains, with zones of inhibition ranging between 16 and 35 mm. Minimum inhibitory concentrations of ethyl acetate extracts ranged from 0.21 to 12.17 µg/mL, with the highest inhibitory effect against S. aureus ranging between 0.21 and 0.29 µg/mL. Some strains (CSK3, CSW2, CSU1 and CSG1) also displayed cytotoxic activity against the HeLa cancer cell line with IC50 values ranging between 3.46 and 9.74 µg/µL, and apparent DNA fragmentation and chromatin condensation. This study indicates that Streptomyces sp. strains isolated from different soil habitats in the UAE can produce antimicrobial compounds that can treat microbial infections. In addition, some strains' cytotoxicity suggests that they are producing bioactive compounds that can lead to drug discovery. [ABSTRACT FROM AUTHOR]