In vitroModels of Host-Microbial Interactions Within the Gastrointestinal Tract

Abstract Background: Ageing is associated with alternations of gastrointestinal (GI) microbiota according to metagenome sequencing. However, the most commonly used sequencing samples were from feces, therefore it remains unknown how the upper gastrointestinal microbiota changes with age and to what extent the fecal can represent the gastrointestinal microbiota. To investigate associations between the microbiota of whole GI tract and ageing, we compared microbial diversity and composition of six GI segments in different phenotypes with a mouse model. Results: Microbial α and β diversity were significantly different between the upper and lower GI tract. The jejunum and ileum samples had significantly lower phylogenetic diversity than large intestinal and stomach did (P < 0.01). About 22.9% core OTUs (n=80) were shared by the whole GI tract, and fecal represented significantly higher microbiota with content from large intestine than content form upper GI tract (82.7% vs. 65.2%, P <0.001). Sutterella, Aggregatibacter, Lactococcus, Lactobacillus and Streptococus were significantly enriched in the upper GI tract, while 14 anaerobes such as Ruminococcus were significantly enriched in the lower GI tract (P < 0.05). The elderly mice had the significant microbial dissimilarity (both in α and β-diversity) with the young- and middle-aged ones. These differences were dependent on GI segments; especially in the lower GI tract, more obvious variations were found. However, the age-associated change was smaller when it compared with the high-fat diet treated mice. Conclusion: The GI microbiota was gradually changed with age and the changes were affected by GI segments. The microbial interactions with host motivate future studies exploring the specified GI microbiota interventions of disease. Keywords: Healthy ageing, Gut microbiota, 16S rRNA sequencing, Gastrointestinal tract, mice

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Habitat Association of Klebsiella Species

Infection Control ◽

10.1017/s0195941700062603 ◽

1985 ◽

Vol 6 (2) ◽

pp. 52-58 ◽

Cited By ~ 111

Author(s):

Susan T. Bagley

Keyword(s):

Drinking Water ◽

Gastrointestinal Tract ◽

Surface Waters ◽

Industrial Effluents ◽

Opportunistic Pathogen ◽

Habitat Associations ◽

Habitat Association ◽

Klebsiella Species ◽

Almost All ◽

Polluted Waters

AbstractThe genus Klebsiella is seemingly ubiquitous in terms of its habitat associations. Klebsiella is a common opportunistic pathogen for humans and other animals, as well as being resident or transient flora (particularly in the gastrointestinal tract). Other habitats include sewage, drinking water, soils, surface waters, industrial effluents, and vegetation. Until recently, almost all these Klebsiella have been identified as one species, ie, K. pneumoniae. However, phenotypic and genotypic studies have shown that “K. pneumoniae” actually consists of at least four species, all with distinct characteristics and habitats. General habitat associations of Klebsiella species are as follows: K. pneumoniae—humans, animals, sewage, and polluted waters and soils; K. oxytoca—frequent association with most habitats; K. terrigena— unpolluted surface waters and soils, drinking water, and vegetation; K. planticola—sewage, polluted surface waters, soils, and vegetation; and K. ozaenae/K. rhinoscleromatis—infrequently detected (primarily with humans).

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A peek in the micro-sized world: a review of design principles, engineering tools, and applications of engineered microbial community

Biochemical Society Transactions ◽

10.1042/bst20190172 ◽

2020 ◽

Vol 48 (2) ◽

pp. 399-409

Author(s):

Baizhen Gao ◽

Rushant Sabnis ◽

Tommaso Costantini ◽

Robert Jinkerson ◽

Qing Sun

Keyword(s):

Microbial Community ◽

Microbial Communities ◽

Environmental Remediation ◽

Real Life ◽

Design Principles ◽

Microbial Interactions ◽

Potential Applications ◽

New Gene ◽

Global Biogeochemical Cycles ◽

Synthetic Microbial Communities

Microbial communities drive diverse processes that impact nearly everything on this planet, from global biogeochemical cycles to human health. Harnessing the power of these microorganisms could provide solutions to many of the challenges that face society. However, naturally occurring microbial communities are not optimized for anthropogenic use. An emerging area of research is focusing on engineering synthetic microbial communities to carry out predefined functions. Microbial community engineers are applying design principles like top-down and bottom-up approaches to create synthetic microbial communities having a myriad of real-life applications in health care, disease prevention, and environmental remediation. Multiple genetic engineering tools and delivery approaches can be used to ‘knock-in' new gene functions into microbial communities. A systematic study of the microbial interactions, community assembling principles, and engineering tools are necessary for us to understand the microbial community and to better utilize them. Continued analysis and effort are required to further the current and potential applications of synthetic microbial communities.

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