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Microbial extracellular electron transfer in the human gastrointestinal tractGratian Ting and Arpita Bose from Washington University in St. Louis discuss the fascinating role that extracellular electron transfer plays within the human gut. The human gut microbiome contains around hundreds of trillions of bacteria, and a great diversity of species. In fact, the number of bacteria in the human gut is similar in number to all the cells in the human body, further signifying the heterogeneity and significance of this microbiota. The habitat filtering of the human gut, defined as the non-random survival of microorganisms in relation to characteristics of the surrounding environment, is influenced by two important factors: host and diet. Disruption of normal host gut processes through various means, could cause cell death and dysbiosis, disrupting host-mediated habitat filtering. However, diet plays a far more common role in this process. Different dietary behaviors exist between individuals from cultural, moral, economic, and other means.
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Trophic level and proteobacteria abundance drive antibiotic resistance levels in fish from coastal New England
Abstract BackgroundThe natural marine environment represents a vast reservoir of antimicrobial resistant bacteria. The wildlife that inhabits this environment plays an important role as the host to these bacteria and in the dissemination of resistance. The relationship between host diet, phylogeny, and trophic level and the microbiome/resistome in marine fish is not fully understood. To further explore this relationship, we utilize shotgun metagenomic sequencing to define the gastrointestinal tract microbiomes of seven different marine vertebrates collected in coastal New England waters. ResultsWe identify inter and intraspecies differences in the gut microbiota of these wild marine fish populations. Furthermore, we find an association between antibiotic resistance genes and host dietary guild, which suggests that higher trophic level organisms have a greater abundance of resistance genes. Additionally, we demonstrate that antibiotic resistance gene burden is positively correlated with Proteobacteria abundance in the microbiome. Lastly, we identify dietary signatures within the gut of these fish and find evidence of possible dietary selection for bacteria with specific carbohydrate utilization potential. ConclusionsThis work establishes a link between host lifestyle/dietary guild, and microbiome composition and the abundance of antibiotic resistance genes within the gastrointestinal tract of marine organisms. We expand the current understanding of marine organism-associated microbial communities and their role as reservoirs of antimicrobial resistance genes.
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- Award ID(s):
- 1655221
- PAR ID:
- 10400479
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- Animal Microbiome
- Volume:
- 5
- Issue:
- 1
- ISSN:
- 2524-4671
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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