gen. nov., sp. nov., a member of the family , isolated from the hindgut of the marine herbivorous fish .

A Gram-stain-negative, non-spore-forming, rod-shaped, obligately anaerobic bacterium, designated strain BP47G, was isolated from the hindgut of a silver drummer () fish collected from the Hauraki Gulf, New Zealand. Phylogenetic analysis based on the 16S rRNA gene sequence of the isolate indicated that it belonged to the family in the phylum . The gene sequence of BP47G was most similar to with 95.

Pre-analytical challenges from adsorptive losses associated with thiamine analysis.

Thiamine (vitamin B1) is an essential vitamin serving in its diphosphate form as a cofactor for enzymes in the citric acid cycle and pentose-phosphate pathways. Its concentration reported in the pM and nM range in environmental and clinical analyses prompted our consideration of the components used in pre-analytical processing, including the selection of filters, filter apparatuses, and sample vials. The seemingly innocuous use of glass fiber filters, glass filter flasks, and glass vials, ubiquitous in laboratory analysis of clinical and environmental samples, led to marked thiamine losses.

The exceptional form and function of the giant bacterium Epulopiscium viviparus revolves around its sodium motive force.

spp. are the largest known heterotrophic bacteria; a large cigar-shaped individual is a million times the volume of . To better understand the metabolic potential and relationship of sp.

Helping students see bacteria in 3D: cellular models increase student learning about cell size and diffusion.

In the microbial world, cell size and shape impact physiology, but students struggle to visualize spatial relationships between cells and macromolecules. In prokaryotic cells, cell size is limited by reliance on diffusion for nutrient uptake and the transport of nutrients within the cell. Cells must also meet a minimum size threshold to accommodate essential cellular components such as ribosomes and DNA.

gen. nov., sp. nov., a member of the family , isolated from the hindgut of the marine herbivorous fish .

A Gram-stain-negative, non-spore-forming, rod-shaped, obligately anaerobic bacterium, designated strain BP5G, was isolated from the hindgut of a silver drummer () fish collected from the Hauraki Gulf, New Zealand. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that the isolate belonged to the family in the phylum and was most closely related to with 94.06 % sequence identity.

Host individual and gut location are more important in gut microbiota community composition than temporal variation in the marine herbivorous fish Kyphosus sydneyanus.

Background: Gut microbiota play a key role in the nutrition of many marine herbivorous fishes through hindgut fermentation of seaweed. Gut microbiota composition in the herbivorous fish Kyphosus sydneyanus (family Kyphosidae) varies between individuals and gut sections, raising two questions: (i) is community composition stable over time, especially given seasonal shifts in storage metabolites of dietary brown algae, and (ii) what processes influence community assembly in the hindgut?

Results: We examined variation in community composition in gut lumen and mucosa samples from three hindgut sections of K. sydneyanus collected at various time points in 2020 and 2021 from reefs near Great Barrier Island, New Zealand.

Microbial circadian clocks: host-microbe interplay in diel cycles.

Background: Circadian rhythms, observed across all domains of life, enable organisms to anticipate and prepare for diel changes in environmental conditions. In bacteria, a circadian clock mechanism has only been characterized in cyanobacteria to date. These clocks regulate cyclical patterns of gene expression and metabolism which contribute to the success of cyanobacteria in their natural environments.

Dietary factors potentially impacting thiaminase I-mediated thiamine deficiency.

Fish population declines from thiamine (vitamin B1) deficiency have been widespread in ecologically and economically valuable organisms, ranging from the Great Lakes to the Baltic Sea and, most recently, the California coast. Thiamine deficiencies in predatory fishes are often attributed to a diet of prey fishes with high levels of thiamine-degrading (e.g.

Substrate degradation pathways, conserved functions and community composition of the hindgut microbiota in the herbivorous marine fish Kyphosus sydneyanus.

Symbiotic gut microbiota in the herbivorous marine fish Kyphosus sydneyanus play an important role in digestion by converting refractory algal carbohydrate into short-chain fatty acids. Here we characterised community composition using both 16S rRNA gene amplicon sequencing and shotgun-metagenome sequencing. Sequencing was carried out on lumen and mucosa samples (radial sections) from three axial sections taken from the hindgut of wild-caught fish.

A centimeter-long bacterium with DNA contained in metabolically active, membrane-bound organelles.

Cells of most bacterial species are around 2 micrometers in length, with some of the largest specimens reaching 750 micrometers. Using fluorescence, x-ray, and electron microscopy in conjunction with genome sequencing, we characterized () Thiomargarita magnifica, a bacterium that has an average cell length greater than 9000 micrometers and is visible to the naked eye. These cells grow orders of magnitude over theoretical limits for bacterial cell size, display unprecedented polyploidy of more than half a million copies of a very large genome, and undergo a dimorphic life cycle with asymmetric segregation of chromosomes into daughter cells.

gen. nov., sp. nov., a member of the family , isolated from the hindgut of the marine herbivorous fish .

A Gram-stain-positive, non-spore-forming, rod-shaped, obligately anaerobic bacterium, designated strain BP52G, was isolated from the hindgut of a Silver Drummer () fish collected from the Hauraki Gulf, New Zealand. Phylogenetic analysis based on 16S rRNA gene sequencing indicated that the isolate belonged to the family in the phylum Firmicutes and was most closely related to with 93.3 % sequence identity.

Distinct microbiota composition and fermentation products indicate functional compartmentalization in the hindgut of a marine herbivorous fish.

Many marine herbivorous fishes harbour diverse microbial communities in the hindgut that can play important roles in host health and nutrition. Kyphosus sydneyanus is a temperate marine herbivorous fish that feeds predominantly on brown seaweeds. We employed 16S rRNA gene amplicon sequencing and gas chromatography to characterize microbial communities and their metabolites in different hindgut regions of six K.

Challenges Faced by Highly Polyploid Bacteria with Limits on DNA Inheritance.

Most studies of bacterial reproduction have centered on organisms that undergo binary fission. In these models, complete chromosome copies are segregated with great fidelity into two equivalent offspring cells. All genetic material is passed on to offspring, including new mutations and horizontally acquired sequences.

Periplasmic binding protein-based magnetic isolation and detection of thiamine in complex biological matrices.

Deficiencies in thiamine (vitamin B1) cause a host of neurological and reproductive impairments yielding morbidity and mortality across environmental and clinical realms. In a technique analogous to immunomagnetic separation, we introduce the use of thiamine periplasmic binding protein (TBP)-conjugated magnetic beads to isolate thiamine from complex matrices. TBP expressed in Escherichia coli is highly specific to thiamine and provides an alternative to antibodies for this non-immunogenic target.

Recombination contributes to population diversification in the polyploid intestinal symbiont Epulopiscium sp. type B.

Epulopiscium sp. type B (Lachnospiraceae) is an exceptionally large, highly polyploid, intestinal symbiont of the coral reef dwelling surgeonfish Naso tonganus. These obligate anaerobes do not form mature endospores and reproduce solely through the production of multiple intracellular offspring.

Thiaminase I Provides a Growth Advantage by Salvaging Precursors from Environmental Thiamine and Its Analogs in Burkholderia thailandensis.

Thiamine is essential to life, as it serves as a cofactor for enzymes involved in critical carbon transformations. Many bacteria can synthesize thiamine, while thiamine auxotrophs must obtain it or its precursors from the environment. Thiaminases degrade thiamine by catalyzing the base-exchange substitution of thiazole with a nucleophile, and thiaminase I specifically has been implicated in thiamine deficiency syndromes in animals.

Competition for vitamin B1 (thiamin) structures numerous ecological interactions.

Thiamin (vitamin B1) is a cofactor required for essential biochemical reactions in all living organisms, yet free thiamin is scarce in the environment. The diversity of biochemical pathways involved in the acquisition, degradation, and synthesis of thiamin indicates that organisms have evolved numerous ecological strategies for meeting this nutritional requirement. In this review we synthesize information from multiple disciplines to show how the complex biochemistry of thiamin influences ecological outcomes of interactions between organisms in environments ranging from the open ocean and the Australian outback to the gastrointestinal tract of animals.

The Gut Microbiota Provisions Thiamine to Its Host.

The microbiota of has a substantial impact on host physiology and nutrition. Some effects may involve vitamin provisioning, but the relationships between microbe-derived vitamins, diet, and host health remain to be established systematically. We explored the contribution of microbiota in supplying sufficient dietary thiamine (vitamin B) to support at different stages of its life cycle.

Genomic insights into the thiamin metabolism of NRRL B-4156 and NRRL B-23460.

is the model organism for studying thiaminase I, an enigmatic extracellular enzyme. Originally isolated from the feces of clinical patients suffering from thiamin deficiency, has been implicated in thiamin deficiencies in humans and other animals due to its ability to produce this thiamin-degrading enzyme. Its close relative, also produces thiaminase I and was originally isolated from dead honeybee larvae, though it has not been reported to be a honeybee pathogen.

Developmental stage influences chromosome segregation patterns and arrangement in the extremely polyploid, giant bacterium Epulopiscium sp. type B.

Few studies have described chromosomal dynamics in bacterial cells with more than two complete chromosome copies or described changes with respect to development in polyploid cells. We examined the arrangement of chromosomal loci in the very large, highly polyploid, uncultivated intestinal symbiont Epulopiscium sp. type B using fluorescent in situ hybridization.

Insights into the single cell draft genome of "Candidatus Achromatium palustre".

"Candidatus Achromatium palustre" was recently described as the first marine representative of the Achromatium spp. in the Thiotrichaceae - a sister lineage to the Chromatiaceae in the Gammaproteobacteria. Achromatium spp.

Metatranscriptomic discovery of plant biomass-degrading capacity from grass carp intestinal microbiomes.

Despite the economic importance of fish, the ecology and metabolic capacity of fish microbiomes are largely unknown. Here, we sequenced the metatranscriptome of the intestinal microbiota of grass carp, Ctenopharyngodon idellus, a freshwater herbivorous fish species. Our results confirmed previous work describing the bacterial composition of the microbiota at the phylum level as being dominated by Firmicutes, Fusobacteria, Proteobacteria and Bacteriodetes.

Sporulation in Bacteria: Beyond the Standard Model.

Endospore formation follows a complex, highly regulated developmental pathway that occurs in a broad range of Firmicutes. Although Bacillus subtilis has served as a powerful model system to study the morphological, biochemical, and genetic determinants of sporulation, fundamental aspects of the program remain mysterious for other genera. For example, it is entirely unknown how most lineages within the Firmicutes regulate entry into sporulation.

Small but Mighty: Cell Size and Bacteria.

Our view of bacteria is overwhelmingly shaped by their diminutive nature. The most ancient of organisms, their very presence was not appreciated until the 17th century with the invention of the microscope. Initially, viewed as "bags of enzymes," recent advances in imaging, molecular phylogeny, and, most recently, genomics have revealed incredible diversity within this previously invisible realm of life.