ID CYSI_XANAC Reviewed; 568 AA. AC Q8PHC8; DT 03-NOV-2009, integrated into UniProtKB/Swiss-Prot. DT 01-OCT-2002, sequence version 1. DT 13-SEP-2023, entry version 113. DE RecName: Full=Sulfite reductase [NADPH] hemoprotein beta-component {ECO:0000255|HAMAP-Rule:MF_01540}; DE Short=SiR-HP {ECO:0000255|HAMAP-Rule:MF_01540}; DE Short=SiRHP {ECO:0000255|HAMAP-Rule:MF_01540}; DE EC=1.8.1.2 {ECO:0000255|HAMAP-Rule:MF_01540}; GN Name=cysI {ECO:0000255|HAMAP-Rule:MF_01540}; OrderedLocusNames=XAC3331; OS Xanthomonas axonopodis pv. citri (strain 306). OC Bacteria; Pseudomonadota; Gammaproteobacteria; Xanthomonadales; OC Xanthomonadaceae; Xanthomonas. OX NCBI_TaxID=190486; RN [1] RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. RC STRAIN=306; RX PubMed=12024217; DOI=10.1038/417459a; RA da Silva A.C.R., Ferro J.A., Reinach F.C., Farah C.S., Furlan L.R., RA Quaggio R.B., Monteiro-Vitorello C.B., Van Sluys M.A., Almeida N.F. Jr., RA Alves L.M.C., do Amaral A.M., Bertolini M.C., Camargo L.E.A., Camarotte G., RA Cannavan F., Cardozo J., Chambergo F., Ciapina L.P., Cicarelli R.M.B., RA Coutinho L.L., Cursino-Santos J.R., El-Dorry H., Faria J.B., RA Ferreira A.J.S., Ferreira R.C.C., Ferro M.I.T., Formighieri E.F., RA Franco M.C., Greggio C.C., Gruber A., Katsuyama A.M., Kishi L.T., RA Leite R.P., Lemos E.G.M., Lemos M.V.F., Locali E.C., Machado M.A., RA Madeira A.M.B.N., Martinez-Rossi N.M., Martins E.C., Meidanis J., RA Menck C.F.M., Miyaki C.Y., Moon D.H., Moreira L.M., Novo M.T.M., RA Okura V.K., Oliveira M.C., Oliveira V.R., Pereira H.A., Rossi A., RA Sena J.A.D., Silva C., de Souza R.F., Spinola L.A.F., Takita M.A., RA Tamura R.E., Teixeira E.C., Tezza R.I.D., Trindade dos Santos M., RA Truffi D., Tsai S.M., White F.F., Setubal J.C., Kitajima J.P.; RT "Comparison of the genomes of two Xanthomonas pathogens with differing host RT specificities."; RL Nature 417:459-463(2002). CC -!- FUNCTION: Component of the sulfite reductase complex that catalyzes the CC 6-electron reduction of sulfite to sulfide. This is one of several CC activities required for the biosynthesis of L-cysteine from sulfate. CC {ECO:0000255|HAMAP-Rule:MF_01540}. CC -!- CATALYTIC ACTIVITY: CC Reaction=3 H2O + hydrogen sulfide + 3 NADP(+) = 4 H(+) + 3 NADPH + CC sulfite; Xref=Rhea:RHEA:13801, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, CC ChEBI:CHEBI:17359, ChEBI:CHEBI:29919, ChEBI:CHEBI:57783, CC ChEBI:CHEBI:58349; EC=1.8.1.2; Evidence={ECO:0000255|HAMAP- CC Rule:MF_01540}; CC -!- COFACTOR: CC Name=siroheme; Xref=ChEBI:CHEBI:60052; CC Evidence={ECO:0000255|HAMAP-Rule:MF_01540}; CC Note=Binds 1 siroheme per subunit. {ECO:0000255|HAMAP-Rule:MF_01540}; CC -!- COFACTOR: CC Name=[4Fe-4S] cluster; Xref=ChEBI:CHEBI:49883; CC Evidence={ECO:0000255|HAMAP-Rule:MF_01540}; CC Note=Binds 1 [4Fe-4S] cluster per subunit. {ECO:0000255|HAMAP- CC Rule:MF_01540}; CC -!- PATHWAY: Sulfur metabolism; hydrogen sulfide biosynthesis; hydrogen CC sulfide from sulfite (NADPH route): step 1/1. {ECO:0000255|HAMAP- CC Rule:MF_01540}. CC -!- SUBUNIT: Alpha(8)-beta(8). The alpha component is a flavoprotein, the CC beta component is a hemoprotein. {ECO:0000255|HAMAP-Rule:MF_01540}. CC -!- SIMILARITY: Belongs to the nitrite and sulfite reductase 4Fe-4S domain CC family. {ECO:0000255|HAMAP-Rule:MF_01540}. CC --------------------------------------------------------------------------- CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms CC Distributed under the Creative Commons Attribution (CC BY 4.0) License CC --------------------------------------------------------------------------- DR EMBL; AE008923; AAM38174.1; -; Genomic_DNA. DR RefSeq; WP_011052200.1; NC_003919.1. DR AlphaFoldDB; Q8PHC8; -. DR SMR; Q8PHC8; -. DR STRING; 190486.XAC3331; -. DR EnsemblBacteria; AAM38174; AAM38174; XAC3331. DR GeneID; 66912382; -. DR KEGG; xac:XAC3331; -. DR eggNOG; COG0155; Bacteria. DR HOGENOM; CLU_001975_3_2_6; -. DR OMA; MGMTHGD; -. DR UniPathway; UPA00140; UER00207. DR Proteomes; UP000000576; Chromosome. DR GO; GO:0009337; C:sulfite reductase complex (NADPH); IEA:InterPro. DR GO; GO:0051539; F:4 iron, 4 sulfur cluster binding; IEA:UniProtKB-KW. DR GO; GO:0020037; F:heme binding; IEA:InterPro. DR GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-KW. DR GO; GO:0050661; F:NADP binding; IEA:InterPro. DR GO; GO:0004783; F:sulfite reductase (NADPH) activity; IEA:UniProtKB-UniRule. DR GO; GO:0019344; P:cysteine biosynthetic process; IEA:UniProtKB-KW. DR GO; GO:0070814; P:hydrogen sulfide biosynthetic process; IEA:UniProtKB-UniRule. DR GO; GO:0000103; P:sulfate assimilation; IEA:UniProtKB-UniRule. DR Gene3D; 3.30.413.10; Sulfite Reductase Hemoprotein, domain 1; 2. DR HAMAP; MF_01540; CysI; 1. DR InterPro; IPR011786; CysI. DR InterPro; IPR005117; NiRdtase/SiRdtase_haem-b_fer. DR InterPro; IPR036136; Nit/Sulf_reduc_fer-like_dom_sf. DR InterPro; IPR006067; NO2/SO3_Rdtase_4Fe4S_dom. DR InterPro; IPR045169; NO2/SO3_Rdtase_4Fe4S_prot. DR InterPro; IPR045854; NO2/SO3_Rdtase_4Fe4S_sf. DR InterPro; IPR006066; NO2/SO3_Rdtase_FeS/sirohaem_BS. DR NCBIfam; TIGR02041; CysI; 1. DR PANTHER; PTHR11493:SF47; SULFITE REDUCTASE [NADPH] SUBUNIT BETA; 1. DR PANTHER; PTHR11493; SULFITE REDUCTASE [NADPH] SUBUNIT BETA-RELATED; 1. DR Pfam; PF01077; NIR_SIR; 1. DR Pfam; PF03460; NIR_SIR_ferr; 2. DR PRINTS; PR00397; SIROHAEM. DR SUPFAM; SSF56014; Nitrite and sulphite reductase 4Fe-4S domain-like; 2. DR SUPFAM; SSF55124; Nitrite/Sulfite reductase N-terminal domain-like; 2. DR PROSITE; PS00365; NIR_SIR; 1. PE 3: Inferred from homology; KW 4Fe-4S; Amino-acid biosynthesis; Cysteine biosynthesis; Heme; Iron; KW Iron-sulfur; Metal-binding; NADP; Oxidoreductase. FT CHAIN 1..568 FT /note="Sulfite reductase [NADPH] hemoprotein beta- FT component" FT /id="PRO_0000388527" FT BINDING 425 FT /ligand="[4Fe-4S] cluster" FT /ligand_id="ChEBI:CHEBI:49883" FT /evidence="ECO:0000255|HAMAP-Rule:MF_01540" FT BINDING 431 FT /ligand="[4Fe-4S] cluster" FT /ligand_id="ChEBI:CHEBI:49883" FT /evidence="ECO:0000255|HAMAP-Rule:MF_01540" FT BINDING 470 FT /ligand="[4Fe-4S] cluster" FT /ligand_id="ChEBI:CHEBI:49883" FT /evidence="ECO:0000255|HAMAP-Rule:MF_01540" FT BINDING 474 FT /ligand="[4Fe-4S] cluster" FT /ligand_id="ChEBI:CHEBI:49883" FT /evidence="ECO:0000255|HAMAP-Rule:MF_01540" FT BINDING 474 FT /ligand="siroheme" FT /ligand_id="ChEBI:CHEBI:60052" FT /ligand_part="Fe" FT /ligand_part_id="ChEBI:CHEBI:18248" FT /note="axial binding residue" FT /evidence="ECO:0000255|HAMAP-Rule:MF_01540" SQ SEQUENCE 568 AA; 62418 MW; 4E86EDBFF11AE961 CRC64; MSHSVEDIKS ESRRLRGSLE QSLADAVTGA LREDDQTLIK YHGSYQQDDR DIRDERRRQK LEPAYQFMIR TRTPGGVITP TQWLALDGIA TRYANHSLRI TTRQAFQFHG VIKRELKATM QAINATLIDT LAACGDVNRN VQVAANPLLS QAHATLYADA ARVSEHLLPN TRAYYEIWLD EERVSGSGSE DEPIYGERYL PRKFKIGFAA PPLNDVDVFA NDLGFIAILR DGQLLGYNVS IGGGMGASHG DAETWPRVAN VIGFVTREQL LDIATAVVTT QRDFGNRAVR KRARFKYTID DHGLDTIVAE IARRAGFALQ PAQPFAFDHN GDRYGWVEGE DGLWHLTLSL PAGRIADTDT AAHLSGLRAI AQLNVGEFRM TPNQNLVIAG VLASERARVD ALVAHYGLDA GNQSATALAR GAMACVALPT CGLAMAEAER YLPDFGAALQ PLLQQHGLAE TPIVLRLSGC PNGCSRPYLA EIALVGKAPG RYNLMLGGDR RGQRLNTLYR ENITEPEILA ALEPLLARYA AERDHANDEG FGDFLHRAGV IALPPYPTHR RLDLELLA //