Search results for "bacteroidetes"
showing 10 items of 53 documents
Prophages and Past Prophage-Host Interactions Revealed by CRISPR Spacer Content in a Fish Pathogen
2020
The role of prophages in the evolution, diversification, or virulence of the fish pathogen Flavobacterium columnare has not been studied thus far. Here, we describe a functional spontaneously inducing prophage fF4 from the F. columnare type strain ATCC 23463, which is not detectable with commonly used prophage search methods. We show that this prophage type has a global distribution and is present in strains isolated from Finland, Thailand, Japan, and North America. The virions of fF4 are myoviruses with contractile tails and infect only bacterial strains originating from Northern Finland. The fF4 resembles transposable phages by similar genome organization and several gene orthologs. Addit…
Profiling of Protein Degraders in Cultures of Human Gut Microbiota
2019
Unabsorbed proteins reach the colon and are fermented by the microbiota, yielding a variety of harmful metabolites. In the present study, a 16S rRNA gene survey identified the bacterial taxa flourishing in 11 batch fermentations with proteins and peptones as the sole fermentable substrates, inoculated with the feces of six healthy adults. Organic acids, ammonia, and indole resulting from protein breakdown and fermentation accumulated in all of the cultures. Analysis of differential abundances among time-points identified Enterobacteriaceae, Burkholderiaceae, and Desulfovibrionaceae (including Esherichia-Shigella, Sutterella, Parasutterella, and Bilophila) among the bacteria that especially …
Comparative Genomics of Blattabacterium cuenoti: The Frozen Legacy of an Ancient Endosymbiont Genome
2013
Many insect species have established long-term symbiotic relationships with intracellular bacteria. Symbiosis with bacteria has provided insects with novel ecological capabilities, which have allowed them colonize previously unexplored niches. Despite its importance to the understanding of the emergence of biological complexity, the evolution of symbiotic relationships remains hitherto a mystery in evolutionary biology. In this study, we contribute to the investigation of the evolutionary leaps enabled by mutualistic symbioses by sequencing the genome of Blattabacterium cuenoti, primary endosymbiont of the omnivorous cockroach Blatta orientalis, and one of the most ancient symbiotic associa…
Pathogens and host immunity in the ancient human oral cavity.
2014
Calcified dental plaque (dental calculus) preserves for millennia and entraps biomolecules from all domains of life and viruses. We report the first high-resolution taxonomic and protein functional characterization of the ancient oral microbiome and demonstrate that the oral cavity has long served as a reservoir for bacteria implicated in both local and systemic disease. We characterize: (i) the ancient oral microbiome in a diseased state, (ii) 40 opportunistic pathogens, (iii) the first evidence of ancient human-associated putative antibiotic resistance genes, (iv) a genome reconstruction of the periodontal pathogen Tannerella forsythia, (v) 239 bacterial and 43 human proteins, allowing co…
Marinifilum flexuosum sp. nov., a new Bacteroidetes isolated from coastal Mediterranean Sea water and emended description of the genus Marinifilum Na…
2012
Abstract A facultatively anaerobe, moderately halophilic, Gram-negative, filamentous, non motile and unpigmented bacterium, designated M30 T , was isolated from coastal Mediterranean Sea water in Valencia, Spain. Phylogenetic analysis based on 16S rRNA sequences placed this strain in the phylum “ Bacteroidetes ” with Marinifilum fragile JC2469 T as its closest relative with 97% sequence similarity. Average nucleotide identity (ANI) values between both strains were far below the 95% threshold value for species delineation (about 89% using BLAST and about 90% using MUMmer). A comprehensive polyphasic study, including morphological, biochemical, physiological, chemotaxonomic and phylogenetic d…
The gut as reservoir of antibiotic resistance: microbial diversity of tetracycline resistance in mother and infant.
2011
The microbiota in the human gastrointestinal tract (GIT) is highly exposed to antibiotics, and may be an important reservoir of resistant strains and transferable resistance genes. Maternal GIT strains can be transmitted to the offspring, and resistances could be acquired from birth. This is a case study using a metagenomic approach to determine the diversity of microorganisms conferring tetracycline resistance (Tc(r)) in the guts of a healthy mother-infant pair one month after childbirth, and to investigate the potential for horizontal transfer and maternal transmission of Tc(r) genes. Fecal fosmid libraries were functionally screened for Tc(r), and further PCR-screened for specific Tc(r) …
The cockroach Blattella germanica obtains nitrogen from uric acid through a metabolic pathway shared with its bacterial endosymbiont.
2014
Uric acid storedin the fat bodyof cockroaches is a nitrogen reservoirmobilized in times of scarcity. The discovery of urease in Blattabacterium cuenoti, the primary endosymbiont of cockroaches, suggests that the endosymbiont may participate in cockroach nitrogen economy. However, bacterial urease may only be one piece in the entire nitrogen recycling process from insect uric acid. Thus, in addition to the uricolytic pathway to urea, there must be glutamine synthetase assimilating the released ammonia by the urease reaction to enable the stored nitrogen to be metabolically usable. None of the Blattabacterium genomes sequenced to date possess genes encoding for those enzymes. To test the host…
Chryseobacterium potabilaquae sp. nov., Chryseobacterium aquaeductus sp. nov. and Chryseobacterium fistulae sp. nov., from drinking water systems
2021
A polyphasic taxonomic study was conducted on three strains isolated from drinking water systems that had previously been deposited as Chryseobacterium species at the Spanish Type Culture Collection in order to complete their classification. Strains CECT 9293T, CECT 9390T and CECT 9393T were isolated from sites in Barcelona, Spain, in the framework of a project aimed at generating the first MALDI-TOF database specific for bacteria present in water for human consumption. Their partial 16S rRNA sequences showed that their closest relatives among the type strains of Chryseobacterium exhibited 98 % similarity or less, supporting their taxonomic novelty. At the same time, comparison between them…
Pyrosequencing survey of intestinal microbiota diversity in cultured sea bass (Dicentrarchus labrax) fed functional diets.
2014
The routine use of chemotherapy to control bacterial diseases in aquatic populations has resulted in the development and spread of antibiotic resistance. The inclusion of immunostimulants in fish diets (functional diets) is one of the main strategies to solve this threat. This study aimed to analyse the intestinal microbiota of cultured European sea bass (Dicentrarchus labrax) fed two functional diets applying pyrosequencing of PCR-amplified 16S rRNA gene. Quality-filtered reads were assigned to family and genus taxonomic levels using the Ribosomal Database Project classifier. The autochthonous intestinal microbiota of sea bass consisted of two dominant bacterial genera: Dysgonomonas (Bacte…
Culturable endophytic microbial communities in the circumpolar grass,Deschampsia flexuosain a sub-Arctic inland primary succession are habitat and gr…
2014
Summary Little is known about endophytic microbes in cold climate plants and how their communities are formed. We compared culturable putative endophytic bacteria and fungi in the ecologically important circumpolar grass, Deschampsia flexuosa growing in two successional stages of subarctic sand dune (68°29′N). Sequence analyses of partial 16S rRNA and internal transcribed spacer (ITS) sequences of culturable endophytes showed that diverse bacteria and fungi inhabit different tissues of D. flexuosa. A total of 178 bacterial isolates representing seven taxonomic divisions, Alpha, Beta and Gammaproteobacteria, Actinobacteria, Bacteroidetes, Firmicutes and Acidobacteria, and 30 fungal isolates …