Colonocyte metabolism shapes the gut microbiota

Metabolic regulation of microbiota The gut microbiota affects human health, but we are only just beginning to develop a mechanistic understanding of some of the host-microbe interactions involved. Litvak et al. review how host colon epithelial cells mediate the symbiosis. Healthy colonocytes maintain anaerobic conditions in the gut lumen because their metabolism ensures rapid oxygen consumption. Such conditions select for obligate anaerobic organisms. These tend to be those that consume dietary fiber and produce short-chain fatty acids beneficial to the host. If there is a shift in colonocyte metabolism—because of disease, diet, or other damage—the epithelium becomes oxygenated. The presence of oxygen allows expansion of facultative aerobic organisms. Microbes in genera that include pathogens are often oxygen-tolerant, and dysbiosis can be the result. Science , this issue p. eaat9076