The Shape of Vibrio cholerae: An Investigation of the Environmental Effects on Vibrio cholerae Curvature and Their Implications

Abstract

Cholera is the leading diarrheal disease worldwide and is caused by the pathogenic bacterium Vibrio cholerae (V. cholerae). Pathogenesis has been proposed to be aided by V. cholerae’s characteristic curved-rod shape, which provides a swimming motility advantage to infiltrate the intestinal mucosal layer. The degree of curvature is dynamic, and it can be perturbed by mutation of the curvature determinant crvA or growth under media with various carbon sources, specifically in high-sucrose conditions. However, the mechanisms by which V. cholerae experience an inhibition of curvature under high-sucrose medium have only been briefly investigated. The objective of this research is to understand the mechanisms by which V. cholerae’s curvature and life cycle adapt in response to varying growth conditions. By subjecting V. cholerae to a variety of culture media, we discovered that media osmolality and cellular growth rate are not sufficient causes for curvature differences observed between media conditions. We instead suggest that metabolism may modify curvature patterns to result in the emergence of an inhibition of curvature phenotype. In addition, we detected spherical, hyper-curved, and elongated V. cholerae cells in response to an array of carbon sources, with certain sources leading to displacement of curvature determinant localization. This research will better inform the scientific community on the curvature dynamics of V. cholerae and its relationship to its pathogenic behavior. Consequently, these findings may offer insight on how to target virulence in bacteria based on cell shape without selecting for resistant bacteria with antibiotics.