Reviewed, UniProtKB/Swiss-Prot P57502 (CYSI_BUCAI)

Names and origin

Protein names

Recommended name:
    Sulfite reductase [NADPH] hemoprotein beta-component
      Short name=SiR-HP
      Short name=SiRHP
    EC=1.8.1.2

Gene names

Name:	cysI
Ordered Locus Names:	BU427

Organism

Buchnera aphidicola subsp. Acyrthosiphon pisum (Acyrthosiphon pisum symbiotic bacterium) [Complete proteome] [HAMAP]

Taxonomic identifier

118099 [NCBI]

Taxonomic lineage

Bacteria › Proteobacteria › Gammaproteobacteria › Enterobacteriales › Enterobacteriaceae › Buchnera

Protein attributes

Sequence length	569 AA.
Sequence status	Complete.
Protein existence	Inferred from homology.

General annotation (Comments)

Function	Component of the sulfite reductase complex that catalyzes the 6-electron reduction of sulfite to sulfide. This is one of several activities required for the biosynthesis of L-cysteine from sulfate By similarity. HAMAP MF_01540
Catalytic activity	H2S + 3 NADP+ + 3 H2O = sulfite + 3 NADPH. HAMAP MF_01540
Cofactor	Binds 1 siroheme per subunit By similarity. HAMAP MF_01540 Binds 1 4Fe-4S cluster per subunit By similarity. HAMAP MF_01540
Pathway	Sulfur metabolism; hydrogen sulfide biosynthesis; hydrogen sulfide from sulfite (NADPH route): step 1/1. HAMAP MF_01540
Subunit structure	Alpha(8)-beta8. The alpha component is a flavoprotein, the beta component is a hemoprotein By similarity. HAMAP MF_01540
Sequence similarities	Belongs to the nitrite and sulfite reductase 4Fe-4S domain family.

Ontologies

Keywords
Biological process	Amino-acid biosynthesis Cysteine biosynthesis
Ligand	4Fe-4S Heme Iron Iron-sulfur Metal-binding NADP
Molecular function	Oxidoreductase
Technical term	Complete proteome
Gene Ontology (GO)
Biological process	cysteine biosynthetic process Inferred from electronic annotation. Source: UniProtKB-KW hydrogen sulfide biosynthetic process Inferred from electronic annotation. Source: HAMAP oxidation reduction Inferred from electronic annotation. Source: UniProtKB-KW sulfate assimilation Inferred from electronic annotation. Source: HAMAP
Cellular component	sulfite reductase complex (NADPH) Inferred from electronic annotation. Source: InterPro
Molecular function	4 iron, 4 sulfur cluster binding Inferred from electronic annotation. Source: UniProtKB-KW NADP or NADPH binding Inferred from electronic annotation. Source: InterPro heme binding Inferred from electronic annotation. Source: InterPro sulfite reductase (NADPH) activity Inferred from electronic annotation. Source: HAMAP
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 569	569	Sulfite reductase [NADPH] hemoprotein beta-component HAMAP MF_01540		PRO_0000199893
Sites
	Metal binding	433	1	Iron-sulfur (4Fe-4S) By similarity
	Metal binding	439	1	Iron-sulfur (4Fe-4S) By similarity
	Metal binding	478	1	Iron-sulfur (4Fe-4S) By similarity
	Metal binding	482	1	Iron (siroheme axial ligand) By similarity
	Metal binding	482	1	Iron-sulfur (4Fe-4S) By similarity

Sequences

	Sequence		Length	Mass (Da)
	P57502-1 [UniParc]. Last modified December 1, 2000. Version 1. Checksum: 7CC09375A08B8DAB	FASTA	569	65,742
	10 20 30 40 50 60 MNKKFKKIVT EKKLTDAERI KENSNYLRGT ITDDLKNEIT NGFTGDNFSL IRFHGMYQQD 70 80 90 100 110 120 DRDLRIERNE QKLEPRYAMM LRCRLPGGVI KAKKWLKIDY FASKYTLYGT IRLTNRQTFQ 130 140 150 160 170 180 FHGILKKNLK DVHKMLHSIG LDSLATANDV NRNVLCTSNP MESLIHQEAY EWARKISNFL 190 200 210 220 230 240 LPHTKAYAEI WLDQKKIVTT EKEPILGKTY LPRKFKTTVV IPPYNDVDLY ANDMNFVAIT 250 260 270 280 290 300 KNEKIIGFNI LIGGGLSFIH GNKNTWPFLA TEIGYISVEN TLSIAKAIVT TQRDWGNRTD 310 320 330 340 350 360 RANAKTRYTI NNFGLNEFKK EIEKRANVNL KPVREYSFIS RGDRFGWIKD INNNWSLTLF 370 380 390 400 410 420 IQNGRIYDDN DKLFKSGLLK IANIHDGNFR ITSNQNIIIS EVSEKNKNKI EKIALSSGLI 430 440 450 460 470 480 NKSTNLRKNS MACVSFPTCP LAMAEAERML SFFITQLENI MLKYGVEDEV IILRVSGCPN 490 500 510 520 530 540 GCGRSLLAEI GLIGKSIGRY NLYIGGNRIG NRIPKIYKEN ITEQEILIHL KYLIKTWSNE 550 560 RKNKEDFGDF IVRKEFVKEV INPVYDFWS

References

[1]	"Genome sequence of the endocellular bacterial symbiont of aphids Buchnera sp. APS." Shigenobu S., Watanabe H., Hattori M., Sakaki Y., Ishikawa H. Nature 407:81-86(2000) [PubMed: 10993077] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: Tokyo 1998.

Cross-references

Sequence databases
EMBL GenBank DDBJ	BA000003 Genomic DNA. Translation: BAB13125.1.
RefSeq	NP_240239.1.
3D structure databases
SMR	P57502. Positions 80-568.
ModBase	Search...
Genome annotation databases
GeneID	1109775.
GenomeReviews	Gene locus BU427 in contig BA000003_GR.
KEGG	buc:BU427.
Organism-specific databases
CMR	Search...
Phylogenomic databases
HOGENOM	HBG626671.
OMA	QDIGLIA.
PhylomeDB	P57502.
Enzyme and pathway databases
BioCyc	BSP107806:BU427-MONOMER.
Family and domain databases
HAMAP	MF_01540. CysI. [Tree]
InterPro	IPR011786. CysI. IPR005117. NiRdtase/SiRdtase_haem-b_fer. IPR006067. NO2/SO3_Rdtase_4Fe4S_dom. IPR006066. NO2/SO3_Rdtase_FeS/sirohaem_BS. [Graphical view]
Pfam	PF01077. NIR_SIR. 2 hits. PF03460. NIR_SIR_ferr. 2 hits. [Graphical view]
PRINTS	PR00397. SIROHAEM.
TIGRFAMs	TIGR02041. CysI. 1 hit.
PROSITE	PS00365. NIR_SIR. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

CYSI_BUCAI

Accession

Primary (citable) accession number: P57502

Entry history

Integrated into UniProtKB/Swiss-Prot:	December 1, 2000
Last sequence update:	December 1, 2000
Last modified:	February 9, 2010
This is version 59 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HAMAP (High-quality Automated and Manual Annotation of microbial Proteomes)