| Primary Identifier | IPR034683 | Type | Family |
| Short Name | IspD/TarI |
| description | This family consists of cytidylyltransferases IspD and TarI.2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase (IspD) catalyses the formation of 4-diphosphocytidyl-2-C-methyl-D-erythritol from CTP and 2-C-methyl-D-erythritol 4-phosphate (MEP) in the deoxyxylulose pathway of isopentenyl diphosphate (IPP) biosynthesis []. This mevalonate independent pathway that utilizes pyruvate and glyceraldehydes 3-phosphate as starting materials for production of IPP occurs in a variety of bacteria, archaea and plant cells, but is absent in mammals. The isoprenoid pathway is a well known target for anti-infective drug development [, ]. In about twenty percent of bacterial genomes, this protein occurs as IspDF, a bifunctional fusion protein.Ribitol-5-phosphate cytidylyltransferase (TarI) is required for the synthesisof activated ribitol via the wall teichoic acid biosynthesis pathway. The enzyme catalyzes the transfer of the cytidylyl group of CTP to D-ribitol 5-phosphate to form CDP-ribitol [].The human IspD (known as D-ribitol-5-phosphate cytidylyltransferase or isoprenoid synthase domain-containing protein) shows a canonical N-terminal cytidyltransferase domain linked to a C-terminal domain that is absent in cytidyltransferase homologues. It has cytidyltransferase activity toward pentose phosphates, including ribulose 5-phosphate, ribose 5-phosphate, and ribitol 5-phosphate. It is implicated in dystroglycan O-mannosylation [, ]. |
