Gut bacterial aggregates as living gels

eLife

Raghuveer Parthasarathy¹  Brandon H Schlomann² 

[1] Department of Physics and Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States;Department of Physics, Institute of Molecular Biology, and Materials Science Institute, University of Oregon, Eugene, United States;Department of Physics and Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States;

关键词: gut microbiota;    zebrafish;    aggregation;    cluster size;    Zebrafish;   

DOI  :  10.7554/eLife.71105

来源: eLife Sciences Publications, Ltd

【 摘 要 】

The spatial organization of gut microbiota influences both microbial abundances and host-microbe interactions, but the underlying rules relating bacterial dynamics to large-scale structure remain unclear. To this end, we studied experimentally and theoretically the formation of three-dimensional bacterial clusters, a key parameter controlling susceptibility to intestinal transport and access to the epithelium. Inspired by models of structure formation in soft materials, we sought to understand how the distribution of gut bacterial cluster sizes emerges from bacterial-scale kinetics. Analyzing imaging-derived data on cluster sizes for eight different bacterial strains in the larval zebrafish gut, we find a common family of size distributions that decay approximately as power laws with exponents close to −2, becoming shallower for large clusters in a strain-dependent manner. We show that this type of distribution arises naturally from a Yule-Simons-type process in which bacteria grow within clusters and can escape from them, coupled to an aggregation process that tends to condense the system toward a single massive cluster, reminiscent of gel formation. Together, these results point to the existence of general, biophysical principles governing the spatial organization of the gut microbiome that may be useful for inferring fast-timescale dynamics that are experimentally inaccessible.

【 授权许可】

CC BY