HMM Summary Page: TIGR00670

Functionaspartate carbamoyltransferase
Gene SymbolpyrB
Trusted Cutoff236.95
Domain Trusted Cutoff236.95
Noise Cutoff186.45
Domain Noise Cutoff186.45
Isology Typeequivalog
EC Number2.1.3.2
HMM Length304
Mainrole CategoryPurines, pyrimidines, nucleosides, and nucleotides
Subrole CategoryPyrimidine ribonucleotide biosynthesis
Gene Ontology TermGO:0004070: aspartate carbamoyltransferase activity molecular_function
GO:0009220: pyrimidine ribonucleotide biosynthetic process biological_process
AuthorHaft DH
Entry DateJan 13 2000 2:40PM
Last ModifiedFeb 14 2011 3:27PM
CommentAspartate transcarbamylase (ATCase) is an alternate name. PyrB encodes the catalytic chain of aspartate carbamoyltransferase, an enzyme of pyrimidine biosynthesis, which organizes into trimers. In some species, including E. coli and the Archaea but excluding Bacillus subtilis, a regulatory subunit PyrI is also present in an allosterically regulated hexameric holoenzyme. Several molecular weight classes of ATCase are described in MEDLINE:96303527 and often vary within taxa. PyrB and PyrI are fused in Thermotoga maritima. Ornithine carbamoyltransferases are in the same superfamily and form an outgroup.
ReferencesAL Clustalw DR PFAM; PF00185; OTCace; superfamily HMM DR PFAM; PF01948; PyrI; regulatory partner HMM DR ECOCYC; EG10805; pyrB DR EXPERIMENTAL; EGAD|16102|BS1550 DR EXPERIMENTAL; EGAD|13385|EC4245 DR EXPERIMENTAL; EGAD|124709|TM1642 DR OUTGROUP; EGAD|104419|AF1255; ornithine carbamoyltransferase RM 96303527 RT A reappraisal of the diversity and class distribution of aspartate transcarbamoylases in gram-negative bacteria. RA Kenny MJ, McPhail D, Shepherdson M RL Microbiology 1996 Jul;142 ( Pt 7):1873-9 DR HAMAP; MF_00001; 502 of 510
Genome PropertyGenProp0187: pyrimidine (uridine-5'-phosphate) de novo biosynthesis (HMM)