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Structural dynamics of RbmA governs plasticity of Vibrio cholerae biofilms.

ABSTRACT: Biofilm formation is critical for the infection cycle of Vibrio cholerae. Vibrio exopolysaccharides (VPS) and the matrix proteins RbmA, Bap1 and RbmC are required for the development of biofilm architecture. We demonstrate that RbmA binds VPS directly and uses a binary structural switch within its first fibronectin type III (FnIII-1) domain to control RbmA structural dynamics and the formation of VPS-dependent higher-order structures. The structural switch in FnIII-1 regulates interactions in trans with the FnIII-2 domain, leading to open (monomeric) or closed (dimeric) interfaces. The ability of RbmA to switch between open and closed states is important for V. cholerae biofilm formation, as RbmA variants with switches that are locked in either of the two states lead to biofilms with altered architecture and structural integrity.

SUBMITTER: Fong JC

PROVIDER: S-EPMC5605196 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Structural dynamics of RbmA governs plasticity of Vibrio cholerae biofilms.

Fong Jiunn Cn JC Rogers Andrew A Michael Alicia K AK Parsley Nicole C NC Cornell William-Cole WC Lin Yu-Cheng YC Singh Praveen K PK Hartmann Raimo R Drescher Knut K Vinogradov Evgeny E Dietrich Lars Ep LE Partch Carrie L CL Yildiz Fitnat H FH

eLife 20170801

Biofilm formation is critical for the infection cycle of Vibrio cholerae. Vibrio exopolysaccharides (VPS) and the matrix proteins RbmA, Bap1 and RbmC are required for the development of biofilm architecture. We demonstrate that RbmA binds VPS directly and uses a binary structural switch within its first fibronectin type III (FnIII-1) domain to control RbmA structural dynamics and the formation of VPS-dependent higher-order structures. The structural switch in FnIII-1 regulates interaction ...[more]

PMID: 28762945

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