The Gut Microbiome of 54 Mammalian Species

The gut microbiome plays a critical role in many aspects of host life, and the microbial community composition is heavily influenced by the prevailing conditions in the gut environment. Community composition has been suggested to have large implications for conservation efforts, and gut health has become of interest for optimizing animal care in captivity. In this study, we explore the gut microbiome of a wide range of animals in the context of conservation biology. The composition of the gut microbial community of 54 mammalian animal species was investigated using 16S rRNA gene amplicon sequencing. The composition of the gut microbiota clearly reflects diet and the structure of the gastrointestinal system, and it is to a certain degree more similar between closely related animals. Specific clusters of taxa were observed across animals of the same species, diet, and gut morphology. The microbiota retained regardless of captivity status is hypothesized to cover important symbiotic relationships with the host, while the remaining part reflects the artificial living conditions and can therefore be used as a future tool for conservation biologists. For five animal species (giraffes, horses, baboons, elephants, and zebras), it was possible to compare the microbiota of wild and captive individuals. Differences were observed in the proportion of microbiota detected between wild and captive specimens of the same animal species. We propose that the gut microbiota harbours important species, which can potentially serve as indicators for the well-being of the animal and the effect of living in captivity

Bacterial Community Composition and its Functional Potential in Ulcerative Colitis Patients:A Case Study

Ulcerative Colitis (UC) is a chronic inflammatory bowel disease characterized by recurring inflammation in the colon. This study aimed to showcase the challenges related to the characterization of the enteric microbial community structure using 16S rRNA gene amplicon sequencing and its functional potentialusing metagenomic sequencing in five patients with UC during active disease and remission. The results revealed inter-individual and intra-individual differences in the microbial community composition. Differential abundance analysis identified specific genera associated with disease state, such asFaecalibacterium and Anaerostipes, which showed positive- and negative correlations, respectively. Prevotella was observed only during active disease. The high level of inter-individual taxonomicdifferences makes it difficult to link the changes to the disease. Functional analysis identified genes related to virulence and inflammatory bowel disease specifically during active disease. Although the approach showed great potential, it was limited by the vast amount of sequencing effort used on host DNA. Further research with a larger cohort and optimized DNA extraction protocols is needed in order validate the results and explore the functional roles of relevant epithelial-associated bacteria which is essential for unravelling the intricate host-microbiota interactions underlying disease pathogenesis