RT Journal Article
SR Electronic
T1 Host Gut Motility and Bacterial Competition Drive Instability in a Model Intestinal Microbiota
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 052985
DO 10.1101/052985
A1 Travis J. Wiles
A1 Matthew L. Jemielita
A1 Ryan P. Baker
A1 Brandon H. Schlomann
A1 Savannah L. Logan
A1 Julia Ganz
A1 Ellie Melancon
A1 Judith S. Eisen
A1 Karen Guillemin
A1 Raghuveer Parthasarathy
YR 2016
UL http://biorxiv.org/content/early/2016/05/12/052985.abstract
AB The gut microbiota is a complex consortium of microorganisms with the ability to influence important aspects of host health and development. Harnessing this ‘microbial organ’ for biomedical applications requires clarifying the degree to which host and bacterial factors act alone or in combination to govern the stability of specific lineages. To address this we combined bacteriological manipulation and light sheet fluorescence microscopy to monitor the dynamics of a defined two-species microbiota within the vertebrate gut. We observed that the interplay between each population and the gut environment produced distinct spatiotemporal patterns. Consequently, one species dominates while the other experiences dramatic collapses that are well fit by a stochastic mathematical model. Modeling revealed that bacterial competition could only partially explain the observed phenomena, suggesting that a host factor is also important in shaping the community. We hypothesized the host determinant to be gut motility, and tested this mechanism by measuring colonization in hosts with enteric nervous system dysfunction due to mutation in the Hirschsprung disease locus ret. In mutant hosts we found reduced gut motility and, confirming our hypothesis, robust coexistence of both bacterial species. This study provides evidence that host-mediated spatial structuring and stochastic perturbation of communities along with bacterial competition drives population dynamics within the gut. In addition, this work highlights the capacity of the enteric nervous system to affect stability of gut microbiota constituents, demonstrating that the ‘gut-brain axis’ is bidirectional. Ultimately, these findings will help inform disease mitigation strategies focused on engineering the intestinal ecosystem.