2-C-methyl-D-erythritol 2,4-cyclodiphosphate synthase

2-C-methyl-D-erythritol 2,4-cyclodiphosphate synthase (MEcPP synthase, IspF, EC 4.6.1.12) is a zinc-dependent enzyme which participates in the MEP pathway (non-mevalonate pathway) of isoprenoid precursor biosynthesis. It catalyzes the chemical reaction:

4-diphosphocytidyl-2-C-methyl-D-erythritol 2-phosphate $\rightleftharpoons$ 2-C-methyl-D-erythritol 2,4-cyclodiphosphate + CMP

Hence, this enzyme has one substrate, 4-diphosphocytidyl-2-C-methyl-D-erythritol 2-phosphate (CDP-MEP), and two products, 2-C-methyl-D-erythritol 2,4-cyclodiphosphate (MEcPP) and CMP.

The enzyme is considered a phosphorus-oxygen lyase. The systematic name of this enzyme class is 2-phospho-4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol CMP-lyase (cyclizing; 2-C-methyl-D-erythritol 2,4-cyclodiphosphate-forming). Other names in common use include IspF, YgbB and MEcPP synthase.

Structural studies

As of late 2007, 20 structures have been solved for this class of enzymes, with PDB accession codes 1GX1, 1H47, 1H48, 1IV1, 1IV2, 1IV3, 1IV4, 1T0A, 1U3L, 1U3P, 1U40, 1U43, 1VH8, 1VHA, 1W55, 1W57, 1YQN, 2AMT, 2GZL, and 2PMP.