IMP dehydrogenase

IMP dehydrogenase EC 1.1.1.205 (Inosine-5'-monophosphate dehydrogenase) (Inosinic acid dehydrogenaseis) (IMPDH) an enzyme that converts inosine monophosphate to xanthosine monophosphate: IMP dehydrogenase EC 1.1.1.205 (Inosine-5'-monophosphate dehydrogenase) (Inosinic acid dehydrogenaseis) (IMPDH) an enzyme that converts inosine monophosphate to xanthosine monophosphate: It catalyzes the rate-limiting reaction of de novo GTP biosynthesis. IMP dehydrogenase is associated with cell proliferation and is a possible target for cancer chemotherapy. Mammalian and bacterial IMPDHs are tetramers of identical chains. There are two IMP dehydrogenase isozymes in humans. IMP dehydrogenase nearly always contains a long insertion that has two CBS domains within it. The structure of this enzyme is composed of a TIM barrel domain with two CBS domains inserted within a loop. It is inhibited by mycophenolic acid, ribavirin, and 6TGMP (6-thioguanine monophosphate). 6TGMP inhibition prevents purine interconversion and thus the synthesis of purine nucleotides.