Protein Family Models

This is the central domain of a multifunctional enzyme which catalyses the biosynthesis of sirohaem. Both of the catalytic activities of this enzyme (precorrin-2 dehydrogenase EC:1.3.1.76) and sirohydrochlorin ferrochelatase (EC:4.99.1.4) are located in the N-terminal domain of this enzyme, Pfam:PF13241 [1]. [1]. 11980703. The structure of Saccharomyces cerevisiae Met8p, a bifunctional dehydrogenase and ferrochelatase. Schubert HL, Raux E, Brindley AA, Leech HK, Wilson KS, Hill CP, Warren MJ;. EMBO J. 2002;21:2068-2075. (from Pfam)

Date:

2024-10-16

This domain is found in fungi, plants, archaea and bacteria. (from Pfam)

Date:

2024-08-14

Bacterial sulfur metabolism depends on the iron-containing porphinoid sirohaem. CysG, S-adenosyl-L-methionine (SAM)-dependent bis-methyltransferase, dehydrogenase and ferrochelatase, synthesises sirohaem from uroporphyrinogen III via reactions which encompass two branchpoint intermediates in tetrapyrrole biosynthesis, diverting flux first from protoporphyrin IX biosynthesis and then from cobalamin (vitamin B12) biosynthesis. CysG is a dimer of two structurally similar protomers held together asymmetrically through a number of salt-bridges across complementary residues in the CysG_dimeriser region to produce a series of active sites, accounting for CysG's multifunctionality, catalysing four diverse reactions: two SAM-dependent methylations, NAD+-dependent tetrapyrrole dehydrogenation and metal chelation. The CysG_dimeriser region holding the two protomers together is of 74 residues [1]. [1]. 14595395. CysG structure reveals tetrapyrrole-binding features and novel regulation of siroheme biosynthesis. Stroupe ME, Leech HK, Daniels DS, Warren MJ, Getzoff ED;. Nat Struct Biol. 2003;10:1064-1073. (from Pfam)

Date:

2024-10-16

This family uses S-AdoMet in the methylation of diverse substrates. This family includes a related group of bacterial proteins of unknown function, including Swiss:P45528. This family includes the methylase Dipthine synthase. (from Pfam)

Date:

2024-08-14

Multifunctional enzyme consisting of uroporphyrin-III C-methyltransferase, precorrin-2 dehydrogenase and sirohydrochlorin ferrochelatase; catalyzes the methylation of uroporphyrinogen III to form precorrin-2, then catalyzes formation of sirohydrochlorin from precorrin-2 and finally catalyzed the formation of siroheme from sirohydrochlorin

Gene:

cysG

Date:

2021-07-23

This HMM represents enzymes, or enzyme domains, with uroporphyrin-III C-methyltransferase activity. This enzyme catalyzes the first step committed to the biosynthesis of either siroheme or cobalamin (vitamin B12) rather than protoheme (heme). Cobalamin contains cobalt while siroheme contains iron. Siroheme is a cofactor for nitrite and sulfite reductases and therefore plays a role in cysteine biosynthesis; many members of this family are CysG, siroheme synthase, with an additional N-terminal domain and with additional oxidation and iron insertion activities.

Gene:

cobA

Date:

2021-04-27

This 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 2.1.1.107), 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.

Date:

2021-04-27

Date:

2020-10-26