Fig. 1.

Regulation of cell curvature by c-di-GMP allows V. cholerae to optimize both biofilm formation and motility. Fernandez et al. (2) find that elevated levels of c-di-GMP at high cell density promote straightening of V. cholerae cells through regulation of the transcription factors VpsR and VpsT. Constitutively curved or straight mutants were hampered in biofilm formation or motility, respectively. The ability of wild-type cells to shift their shape from straight to curved depending on environmental conditions may provide an evolutionary advantage for surviving environmental transitions.