Cytidylyltransferase, phosphorylation

This enzyme [EC 2.7.7.14], also referred to as ethanol-amine-phosphate cytidylyltransferase and phosphoryl-ethanolamine transferase, catalyzes the reaction of CTP with ethanolamine phosphate to produce CDP-ethanol-amine and pyrophosphate. 

Phosphatidylethanolamines, or cephalins (so-called because they were first obtained from brain tissue), can be synthesized by reactions analogous to those of de novo synthesis of phosphatidylcholine. Ethanolamine is first phosphorylated by ATP and ethanolamine kinase to phosphoethanolamine, which then reacts with CTP to form CDP-ethanolamine. CTPrphosphoethanolamine cytidylyltransferase is not located on the endoplasmic reticulum, nor do fatty acids activate it as they do the analogous enzyme of phosphatidylcholine synthesis. Finally, 1,2-diacylglycerol phosphoethanolamine transferase catalyses the reaction of diacylglycerol with CDP-ethanolamine to form phosphatidylethanolamine. 

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