Publication Abstract from PubMed
Isopentenyl diphosphate:dimethylallyl diphosphate (IPP:DMAPP) isomerase is a key enzyme in the biosynthesis of isoprenoids. The mechanism of the isomerization reaction involves protonation of the unactivated carbon-carbon double bond in the substrate. Analysis of the 1.97 A crystal structure of the inactive C67A mutant of E. coli isopentenyl diphosphate:dimethylallyl diphosphate isomerase complexed with the mechanism-based inactivator 3,4-epoxy-3-methyl-1-butyl diphosphate is in agreement with an isomerization mechanism involving Glu 116, Tyr 104, and Cys 67. In particular, the results are consistent with a mechanism where Glu116 is involved in the protonation step and Cys67 in the elimination step.
Crystal structure of the C67A mutant of isopentenyl diphosphate isomerase complexed with a mechanism-based irreversible inhibitor.,Wouters J, Oudjama Y, Stalon V, Droogmans L, Poulter CD Proteins. 2004 Feb 1;54(2):216-21. PMID:14696183[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
