HMM Summary Page: TIGR01470

Functionsiroheme synthase, N-terminal domain
Trusted Cutoff62.30
Domain Trusted Cutoff62.30
Noise Cutoff43.40
Domain Noise Cutoff43.40
Isology Typesubfamily_domain
HMM Length205
Mainrole CategoryBiosynthesis of cofactors, prosthetic groups, and carriers
Subrole CategoryHeme, porphyrin, and cobalamin
Gene Ontology TermGO:0019354: siroheme biosynthetic process biological_process
GO:0043115: precorrin-2 dehydrogenase activity molecular_function
GO:0051266: sirohydrochlorin ferrochelatase activity molecular_function
AuthorHaft DH
Entry DateMar 14 2002 1:59PM
Last ModifiedFeb 14 2011 3:27PM
CommentThis HMM represents a subfamily of CysG N-terminal region-related sequences. All sequences in the seed alignment for this model are N-terminal regions of known or predicted siroheme synthases. The C-terminal region of each is uroporphyrin-III C-methyltransferase (EC, which catalyzes the first step committed to the biosynthesis of either siroheme or cobalamin (vitamin B12) rather than protoheme (heme). The region represented by this model completes the process of oxidation and iron insertion to yield siroheme. Siroheme is a cofactor for nitrite and sulfite reductases, so siroheme synthase is CysG of cysteine biosynthesis in some organisms.
ReferencesRM 11114933 RT Alternative pathways for siroheme synthesis in Klebsiella aerogenes. RA Kolko MM, Kapetanovich LA, Lawrence JG. RL J Bacteriol 2001 Jan;183(1):328-35 DR HAMAP; MF_01646; 105 of 106
Genome PropertyGenProp0194: siroheme biosynthesis from uroporphrinogen-III (HMM)
GenProp0194: siroheme biosynthesis from uroporphrinogen-III (HMM)