This family consists of the N-terminal region of the CTP synthase protein (EC:6.3.4.2). This family is found in conjunction with Pfam:PF00117 located in the C-terminal region of the protein. CTP synthase catalyses the synthesis of CTP from UTP by amination of the pyrimidine ring at the 4-position [1].

1: Thr-431 and Arg-433 are part of a conserved sequence motif of the glutamine amidotransferase domain of CTP synthases and are involved in GTP activation of the Lactococcus lactis enzyme. Willemoes M; J Biol Chem 2003;278:9407-9411. PMID:12522217