The outer mucus layer hosts a distinct intestinal microbial niche
In collaboration with the Sauer lab, Hai Li & Julien P. Limenitakis from the Maurice Müller Laboratories (DKF), University of Bern, describe in detail the compositional differences between lumen and outer mucus layer of the intestine in mice and its consequence for the present microbiota.
Abstract
The overall composition of the mammalian intestinal microbiota varies between individuals: within each individual there are differences along the length of the intestinal tract related to host nutrition, intestinal motility and secretions. Mucus is a highly regenerative protective lubricant glycoprotein sheet secreted by host intestinal goblet cells; the inner mucus layer is nearly sterile. Here we show that the outer mucus of the large intestine forms a unique microbial niche with distinct communities, including bacteria without specialized mucolytic capability. Bacterial species present in the mucus show differential proliferation and resource utilization compared with the same species in the intestinal lumen, with high recovery of bioavailable iron and consumption of epithelial-derived carbon sources according to their genome-encoded metabolic repertoire. Functional competition for existence in this intimate layer is likely to be a major determinant of microbiota composition and microbial molecular exchange with the host.
Reference
Hai Li, Julien P. Limenitakis, Tobias Fuhrer, Markus B. Geuking, Melissa A. Lawson, Madeleine Wyss, Sandrine Brugiroux, Irene Keller, Jamie A. Macpherson, Sandra Rupp, Bettina Stolp, Jens V. Stein, Bärbel Stecher, Uwe Sauer, Kathy D. McCoy & Andrew J. Macpherson, external pageThe outer mucus layer hosts a distinct intestinal microbial nichecall_made, Nature Communication, in press