AAK_UMPK-like: UMP kinase (UMPK)-like, the microbial/chloroplast uridine monophosphate kinase (uridylate kinase) enzyme that catalyzes UMP phosphorylation and plays a key role in pyrimidine nucleotide biosynthesis. Regulation of this process is via feed-back control and via gene repression of carbamoyl phosphate synthetase (the first enzyme of the pyrimidine biosynthesis pathway). The UMP kinases of E. coli (Ec) and Pyrococcus furiosus (Pf) are known to function as homohexamers, with GTP and UTP being allosteric effectors. Like other related enzymes (carbamate kinase, aspartokinase, and N-acetylglutamate kinase) the E. coli and most bacterial UMPKs have a conserved, N-terminal, lysine residue proposed to function in the catalysis of the phosphoryl group transfer, whereas most archaeal UMPKs appear to lack this residue and the Pyrococcus furiosus structure has an additional Mg ion bound to the ATP molecule which is proposed to function as the catalysis instead. Also included in this CD are the alpha and beta subunits of the Mo storage protein (MosA and MosB) characterized as an alpha4-beta4 octamer containing an ATP-dependent, polynuclear molybdenum-oxide cluster. These and related sequences in this CD are members of the Amino Acid Kinase Superfamily (AAK).
Jiyao W et al.(2023). "The conserved domain database in 2023.",