Flow environment and matrix structure interact to determine spatial competition in Pseudomonas aeruginosa biofilms.

TitleFlow environment and matrix structure interact to determine spatial competition in Pseudomonas aeruginosa biofilms.
Publication TypeJournal Article
Year of Publication2017
AuthorsNadell, CD, Ricaurte, D, Yan, J, Drescher, K, Bassler, B
JournalElife
Volume6
Date Published2017/01/13
ISSN2050-084X
Abstract

Bacteria often live in biofilms, which are microbial communities surrounded by a secreted extracellular matrix. Here, we demonstrate that hydrodynamic flow and matrix organization interact to shape competitive dynamics in Pseudomonas aeruginosa biofilms. Irrespective of initial frequency, in competition with matrix mutants, wild type cells always increase in relative abundance in planar microfluidic devices under simple flow regimes. By contrast, in microenvironments with complex, irregular flow profiles - which are common in natural environments - wild type matrix-producing and isogenic non-producing strains can coexist. This result stems from local obstruction of flow by wild-type matrix producers, which generates regions of near-zero shear that allow matrix mutants to locally accumulate. Our findings connect the evolutionary stability of matrix production with the hydrodynamics and spatial structure of the surrounding environment, providing a potential explanation for the variation in biofilm matrix secretion observed among bacteria in natural environments.

DOI10.7554/eLife.21855
Alternate JournalElife
PubMed ID28084994