In enzymology, a glycerol-3-phosphate cytidylyltransferase () is an enzyme that catalyzes the chemical reaction
Thus, the two substrates of this enzyme are CTP and sn-glycerol 3-phosphate, whereas its two products are diphosphate and CDP-glycerol.
This enzyme belongs to the family of transferases, specifically those transferring phosphorus-containing nucleotide groups (nucleotidyltransferases). The systematic name of this enzyme class is CTP:sn-glycerol-3-phosphate cytidylyltransferase. Other names in common use include CDP-glycerol pyrophosphorylase, cytidine diphosphoglycerol pyrophosphorylase, cytidine diphosphate glycerol pyrophosphorylase, CTP:glycerol 3-phosphate cytidylyltransferase, and Gro-PCT. This enzyme participates in glycerophospholipid metabolism.
As of late 2007, 3 structures have been solved for this class of enzymes, with PDB accession codes , , and .