In enzymology, a putrescine carbamoyltransferase (EC 2.1.3.6) is an enzyme that catalyzes the chemical reaction

carbamoyl phosphate + putrescine ${\displaystyle \rightleftharpoons }$ phosphate + N-carbamoylputrescine

Thus, the two substrates of this enzyme are carbamoyl phosphate and putrescine, whereas its two products are phosphate and N-carbamoylputrescine.

This enzyme belongs to the family of transferases that transfer one-carbon groups, specifically the carboxy- and carbamoyltransferases. The systematic name of this enzyme class is carbamoyl-phosphate:putrescine carbamoyltransferase. Other names in common use include PTCase, putrescine synthase, and putrescine transcarbamylase.

• Roon RJ, Barker HA (1972). "Fermentation of agmatine in Streptococcus faecalis: occurrence of putrescine transcarbamoylase". J. Bacteriol. 109 (1): 44–50. PMC 247249. PMID 4621632.
• Srivenugopal KS, Adiga PR (1981). "Enzymic conversion of agmatine to putrescine in Lathyrus sativus seedlings. Purification and properties of a multifunctional enzyme (putrescine synthase)". J. Biol. Chem. 256 (18): 9532–41. PMID 6895223.