HMM Summary Page: TIGR02064

Functionsulfite reductase, dissimilatory-type alpha subunit
Gene SymboldsrA
Trusted Cutoff392.85
Domain Trusted Cutoff392.85
Noise Cutoff222.85
Domain Noise Cutoff222.85
Isology Typeequivalog
EC Number1.8.99.3
HMM Length402
Mainrole CategoryCentral intermediary metabolism
Subrole CategorySulfur metabolism
Gene Ontology TermGO:0018551: hydrogensulfite reductase activity molecular_function
GO:0019420: dissimilatory sulfate reduction biological_process
AuthorBrinkac L
Entry DateNov 25 2003 2:38PM
Last ModifiedFeb 14 2011 3:27PM
CommentDissimilatory sulfite reductase catalyzes the six-electron reduction of sulfite to sulfide, as the terminal reaction in dissimilatory sulfate reduction. It remains unclear however, whether trithionate and thiosulfate serve as intermediate compounds to sulfide, or as end products of sulfite reduction [1]. Sulfite reductase is a multisubunit enzyme composed of dimers of either alpha/beta or alpha/beta/gamma subunits, each containing a siroheme and iron sulfur cluster prosthetic center [2]. Found in sulfate-reducing bacteria, these genes are commonly located in an unidirectional gene cluster [3]. This model describes the alpha subunit of sulfite reductase.
ReferencesRN [1] RM PMID: 7747930 RT Metabolism of sulfate-reducing prokaryotes. RA Hansen TA RL Antonie Van Leeuwenhoek. 1994;66(1-3):165-85. Review. RN [2] RM PMID: 1555572 RT The third subunit of desulfoviridin-type dissimilatory sulfite reductases. RA Pierik AJ, Duyvis MG, van Helvoort JM, Wolbert RB, Hagen WR. RL Eur J Biochem. 1992 Apr 1;205(1):111-5. RN [3] RM PMID: 11557144 RT A novel organization of the dissimilatory sulfite reductase operon of Thermodesulforhabdus norvegica verified by RT-PCR. RA Larsen O, Lien T, Birkeland NK. RL FEMS Microbiol Lett. 2001 Sep 11;203(1):81-5. DR PFAM; PF01077; Nitrite and sulphite reductase 4Fe-4S domain DR EXPERIEMENTAL; SP|P45574; Desulfovibrio vulgaris; purified protein formed mainly trithionate besides thiosulfate and sulfide in sulfite reduction coupled to hydrogenase and methyl viologen DR OUTGROUP; SP|Q59110; Archaeoglobus fulgidus; Sulfite reductase, dissimilatory-type beta subunit
Genome PropertyGenProp0155: dissimilatory sulfate reduction (HMM)