Cyclic Di-GMP and VpsR Induce the Expression of Type II Secretion in Vibrio cholerae.

is a human pathogen that alternates between growth in environmental reservoirs and infection of human hosts, causing severe diarrhea. The second messenger cyclic di-GMP (c-di-GMP) mediates this transition by controlling a wide range of functions, such as biofilms, virulence, and motility. Here, we report that c-di-GMP induces expression of the extracellular protein secretion () gene cluster, which encodes the type II secretion system (T2SS) in Analysis of the genes confirmed the presence of two promoters located upstream of , the first gene in the operon, one of which is induced by c-di-GMP.