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The role of shear dynamics in biofilm formation.

ABSTRACT: There is growing evidence that individual bacteria sense and respond to changes in mechanical loading. However, the subtle responses of multispecies biofilms to dynamic fluid shear stress are not well documented because experiments often fail to disentangle any beneficial effects of shear stress from those delivered by convective transport of vital nutrients. We observed the development of biofilms with lognormally distributed microcolony sizes in drinking water on the walls of flow channels underflow regimes of increasing complexity. First, where regular vortices induced oscillating wall shear and simultaneously enhanced mass transport, which produced the thickest most extensive biofilms. Second, where unsteady uniform flow imposed an oscillating wall shear, with no enhanced transport, and where the biomass and coverage were only 20% smaller. Finally, for uniform steady flows with constant wall shear where the extent, thickness, and density of the biofilms were on average 60% smaller. Thus, the dynamics of shear stress played a significant role in promoting biofilm development, over and above its magnitude or mass transfer effects, and therefore, mechanosensing may prevail in complex multispecies biofilms which could open up new ways of controlling biofilm structure.

SUBMITTER: Tsagkari E

PROVIDER: S-EPMC9055050 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature

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The role of shear dynamics in biofilm formation.

Tsagkari Erifyli E Connelly Stephanie S Liu Zhaowei Z McBride Andrew A Sloan William T WT

NPJ biofilms and microbiomes 20220429 1

There is growing evidence that individual bacteria sense and respond to changes in mechanical loading. However, the subtle responses of multispecies biofilms to dynamic fluid shear stress are not well documented because experiments often fail to disentangle any beneficial effects of shear stress from those delivered by convective transport of vital nutrients. We observed the development of biofilms with lognormally distributed microcolony sizes in drinking water on the walls of flow channels und ...[more]

PMID: 35487949

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The role of shear dynamics in biofilm formation.

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The role of shear dynamics in biofilm formation.

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