| Accession | TIGR02041 |
| Name | CysI |
| Function | sulfite reductase (NADPH) hemoprotein, beta-component |
| Gene Symbol | cysI |
| Trusted Cutoff | 756.55 |
| Domain Trusted Cutoff | 756.55 |
| Noise Cutoff | 707.50 |
| Domain Noise Cutoff | 707.50 |
| Isology Type | equivalog |
| EC Number | 1.8.1.2 |
| HMM Length | 541 |
| Mainrole Category | Central intermediary metabolism |
| Subrole Category | Sulfur metabolism |
| Gene Ontology Term | GO:0000103: sulfate assimilation biological_process |
| | GO:0004783: sulfite reductase (NADPH) activity molecular_function |
| Author | Brinkac L |
| Entry Date | Oct 28 2003 3:23PM |
| Last Modified | Feb 14 2011 3:27PM |
| Comment | Sulfite reductase (NADPH) catalyzes a six electron reduction of sulfite to sulfide in prokaryotic organisms. It is a complex oligomeric enzyme composed of two different peptides with a subunit composition of alpha(8)-beta(4) [1]. The alpha component, encoded by cysJ, is a flavoprotein containing both FMN and FAD, while the beta component, encoded by cysI, is a siroheme, iron-sulfur protein [1].
In Salmonella typhimurium and Escherichia coli, both the alpha and beta subunits of sulfite reductase are located in a unidirectional gene cluster along with phosphoadenosine phosphosulfate reductase, which catalyzes a two step reduction of PAPS to give free sulfite [2].
In cyanobacteria and plant species, sulfite reductase ferredoxin (EC 1.8.7.1) catalyzes the reduction of sulfite to sulfide [3]. |
| References | RN [1]
RM 7569952
RT Sulfite reductase structure at 1.6 A: evolution and catalysis for reduction of inorganic anions.
RA Crane BR, Siegel LM, Getzoff ED.
RL Science. 1995 Oct 6;270(5233):59-67.
RN [2]
RM 2670946
RT Characterization of the cysJIH regions of Salmonella typhimurium and Escherichia coli B. DNA sequences of cysI and cysH and a model for the siroheme-Fe4S4 active center of sulfite reductase hemoprotein based on amino acid homology with spinach nitrite reductase.
RA Ostrowski J, Wu JY, Rueger DC, Miller BE, Siegel LM, Kredich NM.
RL J Biol Chem. 1989 Sep 15;264(26):15726-37.
RN [3]
RM 8347657
RT The ferredoxin:sulphite reductase gene from Synechococcus PCC7942.
RA Gisselmann G, Klausmeier P, Schwenn JD.
RL Biochim Biophys Acta. 1993 Aug 16;1144(1):102-6.
DR PFAM; PF01077; Nitrite and sulphite reductase 4Fe-4S domain
DR PFAM; PF03460; Nitrite/Sulfite reductase ferredoxin-like half domain
DR PROSITE; PS00365; Nitrite and sulfite reductases iron-sulfur/siroheme-binding site.
DR EXPERIMENTAL; SP|P17846; Escherichia coli; isolated as a homodimer exhibiting phospho-adenylylsulphate reductase (PAPS reductase) activity
DR OUTGROUP; GP|1113082; Plectonema boryanum; nitrite reductase
DR HAMAP; MF_01540; 71 of 72 |
| Genome Property | GenProp0149: sulfate reduction to sulfide, assimilatory (HMM) |
