Structural dynamics of RbmA governs plasticity of Vibrio cholerae biofilms

• Main Authors: Jiunn CN Fong, Andrew Rogers, Alicia K Michael, Nicole C Parsley, William-Cole Cornell, Yu-Cheng Lin, Praveen K Singh, Raimo Hartmann, Knut Drescher, Evgeny Vinogradov, Lars EP Dietrich, Carrie L Partch, Fitnat H Yildiz
• Format: Article
• Language: English
• Published: eLife Sciences Publications Ltd 2017-08-01
• Series: eLife
• Subjects: Vibrio cholerae; biofilm; matrix protein; protease; RbmA; VPS
• Online Access: https://elifesciences.org/articles/26163
• ISSN: 2050-084X

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.