Mechanism of activation of bacterial cellulose synthase by cyclic di-GMP

Cyclic di-GMP (c-di-GMP) regulates a number of bacterial processes, including synthesis of cellulose during biofilm formation. The PilZ domain from bacterial cellulose synthase BcsA–BcsB senses c-di-GMP and activates the enzyme. Now crystal structures of BcsA–BcsB along with functional analysis reveal that binding of c-di-GMP releases a conserved gating loop to allow substrate to enter the active site.