Resilience of small intestinal beneficial bacteria to the toxicity of soybean oil fatty acids
- Max Planck Institute for Developmental Biology, Germany
- Cornell University, United States
- Baylor College of Medicine, United States
- University of Alberta, Canada
Abstract
Over the past century, soybean oil (SBO) consumption in the United States increased dramatically. The main SBO fatty acid, linoleic acid (18:2), inhibits in vitro the growth of lactobacilli, beneficial members of the small intestinal microbiota. Human-associated lactobacilli have declined in prevalence in Western microbiomes, but how dietary changes may have impacted their ecology is unclear. Here, we compared the in vitro and in vivo effects of 18:2 on Lactobacillus reuteri and L. johnsonii. Directed evolution in vitro in both species led to strong 18:2 resistance with mutations in genes for lipid biosynthesis, acid stress, and the cell membrane or wall. Small-intestinal Lactobacillus populations in mice were unaffected by chronic and acute 18:2 exposure, yet harbored both 18:2- sensitive and resistant strains. This work shows that extant small intestinal lactobacilli are protected from toxic dietary components via the gut environment as well as their own capacity to evolve resistance.
Article and author information
Author details
Funding
NIH Office of the Director (DP2OD007444)
- Ruth Emily Ley
Life Sciences Research Foundation (Eli & Edythe Broad Fellow)
- Ruth Emily Ley
Max-Planck-Gesellschaft (Open-access funding)
- Ruth Emily Ley
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All animal experimental procedures were reviewed and approved by the Institutional Animal Care and Usage Committee of Cornell University protocol 2010-0065.
Copyright
© 2018, Di Rienzi et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Resilience of small intestinal beneficial bacteria to the toxicity of soybean oil fatty acids
eLife 7:e32581.
https://doi.org/10.7554/eLife.32581
Further reading
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The microbiome protects beneficial gut bacteria from toxic substances in our diet.
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