The structural basis of cyclic diguanylate signal transduction by PilZ domains

摘要: The second messenger cyclic diguanylate (c-di-GMP) controls the transition between motile and sessile growth in eubacteria, but little is known about proteins that sense its concentration. Bioinformatics analyses suggested PilZ domains bind c-di-GMP allosterically modulate effector pathways. We have determined a 1.9 A crystal structure of bound to VCA0042/PlzD, domain-containing protein from Vibrio cholerae. Either this or another specific required for V. cholerae efficiently infect mice. VCA0042/PlzD comprises C-terminal domain plus an N-terminal with similar β-barrel fold. C-di-GMP contacts seven nine strongly conserved residues domain, including three seven-residue long loop undergoes conformational switch as it wraps around c-di-GMP. This brings into close apposition forming new allosteric interaction surface spans these at their interface. very small size likely explain facile evolutionary diversification domain.