Secreted Proteases Control the Timing of Aggregative Community Formation in Vibrio cholerae

Publication Year
2021

Type

Journal Article
Abstract
Bacteria orchestrate collective behaviors using the cell-cell communication process called quorum sensing (QS). QS relies on the synthesis, release, and group-wide detection of small molecules called autoinducers. In Vibrio cholerae, a multicellular community aggregation program occurs in liquid, during the stationary phase, and in the high-cell-density QS state. Here, we demonstrate that this aggregation program consists of two subprograms. In one subprogram, which we call void formation, structures form that contain few cells but provide a scaffold within which cells can embed. The other subprogram relies on flagellar machinery and enables cells to enter voids. A genetic screen for factors contributing to void formation, coupled with companion molecular analyses, showed that four extracellular proteases, Vca0812, Vca0813, HapA, and PrtV, control the onset timing of both void formation and aggregation; moreover, proteolytic activity is required. These proteases, or their downstream products, can be shared between void-producing and non-void-forming cells and can elicit aggregation in a normally nonaggregating V. cholerae strain. Employing multiple proteases to control void formation and aggregation timing could provide a redundant and irreversible path to commitment to this community lifestyle. IMPORTANCE Bacteria can work as collectives to form multicellular communities. Vibrio cholerae, the bacterium that causes the disease cholera in humans, forms aggregated communities in liquid. Aggregate formation relies on a chemical communication process called quorum sensing. Here, we show that, beyond overarching control by quorum sensing, there are two aggregation subprograms. One subprogram, which we call void formation, creates a scaffold within which cells can embed. The second subprogram, which allows bacteria to enter the scaffold, requires motility. We discovered that four extracellular proteases control the timing of both void formation and aggregation. We argue that, by using redundant proteases, V. cholerae ensures the reliable execution of this community formation process. These findings may provide insight into how V. cholerae persists in the marine environment or colonizes the human host, as both lifestyles are central to the spread of the disease cholera.
Journal
mBio
Volume
12
Pages
e0151821
Date Published
12/2021
Accession Number
34809464
Short Title
mBio

2150-7511Jemielita, MatthewMashruwala, Ameya AValastyan, Julie SWingreen, Ned SBassler, Bonnie LOrcid: 0000-0002-0043-746xR37 GM065859/GM/NIGMS NIH HHS/United StatesK99 GM138764/GM/NIGMS NIH HHS/United StatesR01 GM065859/GM/NIGMS NIH HHS/United StatesR01 GM082938/GM/NIGMS NIH HHS/United StatesHHMI/Howard Hughes Medical Institute/United StatesJournal ArticleResearch Support, N.I.H., ExtramuralResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.2021/11/24mBio. 2021 Dec 21;12(6):e0151821. doi: 10.1128/mBio.01518-21. Epub 2021 Nov 23.