Structure and function of CysG, the multifunctional methyltransferase/dehydrogenase/ferrochelatase for siroheme synthesis
External Resource: Annotation
- Domain Annotation: SCOP/SCOPe Classification
- Domain Annotation: SCOP2 Classification
- Domain Annotation: ECOD Classification
- Domain Annotation: CATH
- Protein Family Annotation
- Gene Ontology: Gene Product Annotation
- InterPro: Protein Family Classification
- Protein Modification Annotation
- Structure Motif: Primary M-CSA Annotation
Domain Annotation: SCOP/SCOPe Classification SCOP-e Database Homepage
Domain Annotation: SCOP2 Classification SCOP2 Database Homepage
| Chains | Type | Family Name | Domain Identifier | Family Identifier | Provenance Source (Version) |
|---|---|---|---|---|---|
| A | SCOP2B Superfamily | Tetrapyrrole methylase | 8001041 | 3000017 | SCOP2B (2022-06-29) |
| A | SCOP2B Superfamily | CysG/Met8-like | 8057834 | 3000045 | SCOP2B (2022-06-29) |
| B | SCOP2 Family | Siroheme synthase-like | 8001039 | 4000066 | SCOP2 (2022-06-29) |
| B | SCOP2 Family | Tetrapyrrole methylase | 8001040 | 4000056 | SCOP2 (2022-06-29) |
| B | SCOP2 Superfamily | CysG/Met8-like | 8057834 | 3000045 | SCOP2 (2022-06-29) |
| B | SCOP2 Superfamily | Tetrapyrrole methylase | 8001041 | 3000017 | SCOP2 (2022-06-29) |
Domain Annotation: ECOD Classification ECOD Database Homepage
| Chains | Family Name | Domain Identifier | Architecture | Possible Homology | Homology | Topology | Family | Provenance Source (Version) |
|---|---|---|---|---|---|---|---|---|
| A | e1pjqA1 | A: alpha-helical domain in siroheme synthase middle domains-like | X: alpha-helical domain in siroheme synthase middle domains-like | H: alpha-helical domain in siroheme synthase middle domains-like | T: CysG_dimeriser | F: | ECOD (20:10:01) | |
| A | e1pjqA2 | A: SSH domain in siroheme synthase middle domains-like | X: SSH domain in siroheme synthase middle domains-like | H: SSH domain in siroheme synthase middle domains-like | T: Sirohm_synth_M | F: | ECOD (20:10:01) | |
| A | e1pjqA3 | A: Rossmann-like | X: Rossmann-related | H: NAD(P)-binding Rossmann-fold domains | T: NAD_binding_7 | F: | ECOD (20:10:01) | |
| A | e1pjqA6 | A: jelly-roll | X: AOC barrel-like | H: AOC barrel-like | T: | F: | ECOD (20:10:01) | |
| B | e1pjqB2 | A: SSH domain in siroheme synthase middle domains-like | X: SSH domain in siroheme synthase middle domains-like | H: SSH domain in siroheme synthase middle domains-like | T: Sirohm_synth_M | F: | ECOD (20:10:01) | |
| B | e1pjqB1 | A: C-terminal subdomain in Lon-related proteases catalytic domains | X: C-terminal subdomain in Lon-related proteases catalytic domains | H: C-terminal subdomain in Lon-related proteases catalytic domains | T: Propep_M14 | F: | ECOD (20:10:01) | |
| B | e1pjqB4 | A: C-terminal subdomain in Lon-related proteases catalytic domains | X: C-terminal subdomain in Lon-related proteases catalytic domains | H: C-terminal subdomain in Lon-related proteases catalytic domains | T: FAD_binding_3 | F: | ECOD (20:10:01) | |
| B | e1pjqB3 | A: F-type ATP synthase subunit b | X: Bacterial cell wall synthesis membrane enzyme MraY-related | H: Bacterial cell wall synthesis membrane enzyme MraY-related | T: Phage_int_SAM_6 | F: | ECOD (20:10:01) |
Domain Annotation: CATH CATH Database Homepage
Protein Family Annotation Pfam Database Homepage
| Chains | Accession | Name | Description | Comments | Source |
|---|---|---|---|---|---|
| PF14824 | Sirohaem biosynthesis protein central (Sirohm_synth_M) | Sirohaem biosynthesis protein central | 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 ... | Domain | |
| PF00590 | Tetrapyrrole (Corrin/Porphyrin) Methylases (TP_methylase) | Tetrapyrrole (Corrin/Porphyrin) Methylases | 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. | Domain | |
| PF13241 | Putative NAD(P)-binding (NAD_binding_7) | Putative NAD(P)-binding | This domain is found in fungi, plants, archaea and bacteria. | Domain | |
| PF10414 | Sirohaem synthase dimerisation region (CysG_dimeriser) | Sirohaem synthase dimerisation region | 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 ... | Domain |
Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage
InterPro: Protein Family Classification InterPro Database Homepage
| Chains | Accession | Name | Type |
|---|---|---|---|
| IPR035996 | Tetrapyrrole methylase superfamily | Homologous Superfamily | |
| IPR014776 | Tetrapyrrole methylase, subdomain 2 | Homologous Superfamily | |
| IPR037115 | Sirohaem synthase, dimerisation domain superfamily | Homologous Superfamily | |
| IPR006366 | Uroporphyrin-III C-methyltransferase | Domain | |
| IPR014777 | Tetrapyrrole methylase, subdomain 1 | Homologous Superfamily | |
| IPR012409 | Sirohaem synthase | Family | |
| IPR028281 | Siroheme synthase, central domain | Domain | |
| IPR019478 | Sirohaem synthase, dimerisation domain | Domain | |
| IPR003043 | Uroporphiryn-III C-methyltransferase, conserved site | Conserved Site | |
| IPR036291 | NAD(P)-binding domain superfamily | Homologous Superfamily | |
| IPR000878 | Tetrapyrrole methylase | Domain | |
| IPR006367 | Sirohaem synthase, N-terminal | Domain | |
| IPR050161 | Siroheme/cobalamin biosynthesis enzyme | Family |
Structure Motif Annotation: Mechanism and Catalytic Site Atlas M-CSA Database Homepage
| Chains | Enzyme Name | Description | Catalytic Residues |
|---|---|---|---|
| uroporphyrinogen-III C-methyltransferase M-CSA #702 | The reference protein (CysG) covers three different domains/functions each component of which can be found as independent proteins in other organisms. This entry relates to the uroporphyrinogen-III C-methyltransferase function (residues 216-448 in the reference protein). This catalytic site catalyses two sequential methylation reactions using S-andenosyl-L-methionine (SAM), the first forming precorrin-1 and the second leading to the formation of precorrin-2. It is the first of three steps leading to the formation of siroheme from uroporphyrinogen III. | EC: 2.1.1.107 (PDB Primary Data) EC: 1 (PDB Primary Data) EC: 4.99.1 (PDB Primary Data) EC: 4.99.1.4 (UniProt) EC: 1.3.1.76 (UniProt) |














