Structural dynamics of RbmA governs plasticity of Vibrio cholerae biofilms
- University of California, Santa Cruz, United States
- University of North Carolina Chapel Hill, United States
- Columbia University, United States
- Max Planck Institute for Terrestrial Microbiology, Germany
- National Research Council, Canada
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.
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Author details
Funding
National Institute of Allergy and Infectious Diseases (RO1AI055987)
- Fitnat H Yildiz
National Institute of General Medical Sciences (GM107069)
- Carrie L Partch
Human Frontier Science Program (CDA00084/2015-C)
- Knut Drescher
National Institute of General Medical Sciences (CA189660)
- Alicia K Michael
National Institute of Allergy and Infectious Diseases (R01 AI103369)
- Lars EP Dietrich
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2017, Fong et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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