The CIAMIB: a Large and Metabolically Diverse Collection of Inflammation-Associated Bacteria from the Murine Gut

mBio. 2022 Apr 26;13(2):e0294921. doi: 10.1128/mbio.02949-21. Epub 2022 Mar 10.

Abstract

Gut inflammation directly impacts the growth and stability of commensal gut microbes and can lead to long-lasting changes in microbiota composition that can prolong or exacerbate disease states. While mouse models are used extensively to investigate the interplay between microbes and the inflamed state, the paucity of cultured mouse gut microbes has hindered efforts to determine causal relationships. To address this issue, we are assembling the Collection of Inflammation-Associated Mouse Intestinal Bacteria (CIAMIB). The initial release of this collection comprises 41 isolates of 39 unique bacterial species, covering 4 phyla and containing 10 previously uncultivated isolates, including 1 novel family and 7 novel genera. The collection significantly expands the number of available Muribaculaceae, Lachnospiraceae, and Coriobacteriaceae isolates and includes microbes from genera associated with inflammation, such as Prevotella and Klebsiella. We characterized the growth of CIAMIB isolates across a diverse range of nutritional conditions and predicted their metabolic potential and anaerobic fermentation capacity based on the genomes of these isolates. We also provide the first metabolic analysis of species within the genus Adlercreutzia, revealing these representatives to be nitrate-reducing and severely restricted in their ability to grow on carbohydrates. CIAMIB isolates are fully sequenced and available to the scientific community as a powerful tool to study host-microbiota interactions. IMPORTANCE Attempts to explore the role of the microbiota in animal physiology have resulted in large-scale efforts to cultivate the thousands of microbes that are associated with humans. In contrast, relatively few lab mouse-associated bacteria have been isolated, despite the fact that the overwhelming number of studies on the microbiota use laboratory mice that are colonized with microbes that are quite distinct from those in humans. Here, we report the results of a large-scale isolation of bacteria from the intestines of laboratory mice either prone to or suffering from gut inflammation. This collection comprises dozens of novel isolates, many of which represent the only cultured representatives of their genus or species. We report their basic growth characteristics and genomes and are making them widely available to the greater research community.

Keywords: Adlercreutzia; Atopobiaceae; Lachnospiraceae; Muribaculaceae; Prevotella; gut inflammation; microbial growth; microbiota.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacteria / genetics
  • Gastrointestinal Microbiome* / physiology
  • Inflammation
  • Mice
  • Microbiota*
  • Symbiosis