HMM Summary Page: TIGR01369

Functioncarbamoyl-phosphate synthase, large subunit
Gene SymbolcarB
Trusted Cutoff1027.00
Domain Trusted Cutoff1027.00
Noise Cutoff469.10
Domain Noise Cutoff469.10
Isology Typeequivalog_domain
EC Number6.3.5.5
HMM Length1052
Mainrole CategoryPurines, pyrimidines, nucleosides, and nucleotides
Subrole CategoryPyrimidine ribonucleotide biosynthesis
Gene Ontology TermGO:0004088: carbamoyl-phosphate synthase (glutamine-hydrolyzing) activity molecular_function
GO:0005951: carbamoyl-phosphate synthase complex cellular_component
GO:0009220: pyrimidine ribonucleotide biosynthetic process biological_process
AuthorHaft DH
Entry DateOct 30 2001 10:37AM
Last ModifiedFeb 14 2011 3:27PM
CommentCarbamoyl-phosphate synthase (CPSase) catalyzes the first committed step in pyrimidine, arginine, and urea biosynthesis. In general, it is a glutamine-dependent enzyme, EC, termed CPSase II in eukaryotes. An exception is the mammalian mitochondrial urea-cycle form, CPSase I, in which the glutamine amidotransferase domain active site Cys on the small subunit has been lost, and the enzyme is ammonia-dependent. In both CPSase I and the closely related, glutamine-dependent CPSase III (allosterically activated by acetyl-glutamate) demonstrated in some other vertebrates, the small and large chain regions are fused in a single polypeptide chain. This HMM represents the large chain of glutamine-hydrolysing carbamoyl-phosphate synthases, or the corresponding regions of larger, multifunctional proteins, as found in all domains of life, and CPSase I forms are considered exceptions within the family. In several thermophilic species (Methanobacterium thermoautotrophicum, Methanococcus jannaschii, Aquifex aeolicus), the large subunit appears split, at different points, into two separate genes.
ReferencesDR EXCEPTION; SP|P31327; EC; Homo sapiens DR EXPERIMENTAL; SP|P00968; Escherichia coli DR HAMAP; MF_01210; 171 of 173
Genome PropertyGenProp0187: pyrimidine (uridine-5'-phosphate) de novo biosynthesis (HMM)