9.B.273. The Phosphatidate Cytidylyltransferase (PCT) Family Phosphatidate cytidylyltransferases, or diacyl glyceride syntehtases, catalyze the reaction of CTP and phosphatidate to form diphosphate and CDP-diacylglycerol, a central liponucleotide for phospholipid biosynthesis. These proteins are of about 270 aas in length and have about 8 TMSs.
Examples:
TC#	Name	Organismal Type	Example
9.B.273.1.1	Phosphatidate cytidylyltransferaseof 385 aas and 9 TM		PCT of Streptomyces zinciresistens

9.B.273.1.2	Phosphatidate cytidylyltransferase of 273 aas and 7 TMSs.		PCT of Burkholderia cenocepacia