Structural insights into the prereaction state of pyruvate decarboxylase from Zymomonas mobilis .

ABSTRACT: Pyruvate decarboxylase (PDC) uses thiamine diphosphate as an essential cofactor to catalyze the formation of acetaldehyde on the pathway of ethanol synthesis. Here we report the crystallographic image of a prereaction intermediate of a bacterial pyruvate decarboxylase prepared by cocrystallizing the enzyme with pyruvate and a stable analogue of the cofactor's activated ylid form. A second crystal structure of PDC in complex with fluoride shows that the ion organizes a water molecule that occludes the pyruvate binding site, accounting for the inhibitory effect of the halide. Also reported is a structure of the cofactor-free apo form, which when compared to the structure of the holo form indicates how thiamine diphosphate organizes the active site pocket of pyruvate decarboxylase to support

SUBMITTER: Pei XY 

PROVIDER: S-EPMC2855724 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature