FUNCTION: Catalyzes the 6-electron reduction of sulfite to sulfide. This is one of several activities required for the biosynthesis of L-cysteine from sulfate. The flavo-protein component catalyzes the electron flow from NADPH -> FAD -> FMN to the hemoprotein component (By similarity).
CATALYTIC ACTIVITY: H₂S + 3 NADP⁺ + 3 H₂O = sulfite + 3 NADPH.
COFACTOR: Binds 1 FAD per subunit (By similarity).
COFACTOR: Binds 1 FMN per subunit (By similarity).
SUBUNIT: Alpha(8)-beta(8). The alpha component is a flavoprotein, the beta component is a hemoprotein (By similarity).
SIMILARITY: Contains 1 FAD-binding FR-type domain.
SIMILARITY: Contains 1 flavodoxin-like domain.

Copyright

Copyrighted by the UniProt Consortium, see http://www.uniprot.org/terms. Distributed under the Creative Commons Attribution-NoDerivs License.

Cross-references

Sequence databases

EMBL

AE013218; AAM67958.1; -; Genomic_DNA.

[EMBL / GenBank / DDBJ] [CoDingSequence]

RefSeq

NP_660747.1; -.

3D structure databases

HSSP

P38038; 1DDG. [HSSP ENTRY / PDB]

ModBase

Q8K9D3.

Enzyme and pathway databases

BioCyc

BAPH198804:BUSG413-MON; -.

Ontologies

GO:0009055;	Molecular function: electron carrier activity (inferred from electronic annotation from InterPro).
GO:0010181;	Molecular function: FMN binding (inferred from electronic annotation from InterPro).
GO:0005506;	Molecular function: iron ion binding (inferred from electronic annotation from InterPro).
GO:0004783;	Molecular function: sulfite reductase (NADPH) activity (inferred from electronic annotation from HAMAP).
GO:0019344;	Biological process: cysteine biosynthetic process (inferred from electronic annotation from InterPro).
GO:0022900;	Biological process: electron transport chain (inferred from electronic annotation from UniProtKB-KW).
GO:0000103;	Biological process: sulfate assimilation (inferred from electronic annotation from HAMAP).
GO:0006810;	Biological process: transport (inferred from electronic annotation from UniProtKB-KW).
QuickGo view.

Family and domain databases

HAMAP

MF_01541; -; 1.
PBIL [Tree]

InterPro

IPR010199; CysJ.
IPR003097; FAD-binding_1.
IPR001094; Flavdoxin_like.
IPR008254; Flavodoxin/NO_synth.
IPR001709; FPN_cyt_redctse.
IPR001433; OxRdtase_FAD/NAD_bd.
Graphical view of domain structure.

Pfam

PF00667; FAD_binding_1; 1.
PF00258; Flavodoxin_1; 1.
PF00175; NAD_binding_1; 1.
Pfam graphical view of domain structure.

PRINTS

PR00369; FLAVODOXIN.
PR00371; FPNCR.

TIGRFAMs

TIGR01931; cysJ; 1.

PROSITE

PS51384; FAD_FR; 1.
PS50902; FLAVODOXIN_LIKE; 1.
PROSITE graphical view of domain structure (profiles).

Genome annotation databases

GeneID

1005748; -.

GenomeReviews

AE013218_GR; BUsg_413.

KEGG

bas:BUsg413; -.

Phylogenomic databases

HOGENOM

Q8K9D3; -.

Genome annotation databases

CMR

Q8K9D3; BUsg_413.

Other

ProtoNet

Q8K9D3.

UniRef

View cluster of proteins with at least 50% / 90% / 100% identity.

Keywords

Amino-acid biosynthesis; Complete proteome; Cysteine biosynthesis; Electron transport; FAD; Flavoprotein; FMN; NADP; Oxidoreductase; Transport.

Features

Feature table viewer

Feature aligner

`Key`	`From To`	`Length`	`Description`	`FTId`
`CHAIN`	`1 602`	`602`	`Sulfite reductase [NADPH] flavoprotein alpha-component.`	`PRO_0000199921`
`DOMAIN`	`68 206`	`139`	`Flavodoxin-like.`
`DOMAIN`	`237 451`	`215`	`FAD-binding FR-type.`
`NP_BIND`	`74 78`	`5`	`FMN (By similarity).`
`NP_BIND`	`154 185`	`32`	`FMN (By similarity).`
`NP_BIND`	`239 291`	`53`	`FAD (By similarity).`
`NP_BIND`	`475 602`	`128`	`NADP (By similarity).`

Sequence information

Length: 602 AA [This is the length of the unprocessed precursor]

Molecular weight: 69930 Da [This is the MW of the unprocessed precursor]

CRC64: FA3793147889B7B3 [This is a checksum on the sequence]

        10         20         30         40         50         60 
MKNKNPFNIF FPLSLDKIEN LEKIKKNCSS IQYAWLSGYF WNLANQTPSR LICEKNEFFR 

        70         80         90        100        110        120 
KDNEEKIITI ISASQTGNAR QLAKRFNKYL KNENKKTNLI DAADYNFKKI KNERFLILII 

       130        140        150        160        170        180 
STQGEGEPPE EALSFYKFIM SKKAPRLENL HYSVFGLGDV SYNLFCQAGK DFDKRFSELG 

       190        200        210        220        230        240 
GKSLLHRLDS DIEYESNYIQ WSEELLLAIN KIDVSTCSVF KKNDKKNFID KLNYTKYKPA 

       250        260        270        280        290        300 
VATVLLNQKI TGRNSTKDVH HIELDITNSN IVYTPGDALG VWYQNSSQLI KQILKLLSIR 

       310        320        330        340        350        360 
ISDKVKVKDK IITIFEALKK NFELTTNTKH IIQKYTDVTQ NKFLKKIISD NKKLNNYVKK 

       370        380        390        400        410        420 
TPLLKMIYDH PKKLSSQQLI SILRPLKPRL YSISSSQSEM NDEVHITVGV VKKQISGTIH 

       430        440        450        460        470        480 
LGGSSSYLSQ FLKIDDSVKI FVEEKSNFRL PENKDVPIIM IGSGTGIAPF RAFIQQRDND 

       490        500        510        520        530        540 
KATGKNWIFF GNPNFTEDFL YQLEWQKYLK KKLLTKMSLA WSRDQKEKIY VQDKIRENGK 

       550        560        570        580        590        600 
ELWEWVNQGA QIYVCGNASK MAKDVEKELL DVFSKNGSMD IEESSEFLNN LRITRRYQRD 


VY

Q8K9D3 in FASTA format

View entry in original UniProtKB/Swiss-Prot format
View entry in raw text format (no links)
Report form for errors/updates in this UniProtKB/Swiss-Prot entry

	BLAST submission on ExPASy/SIB or at NCBI (USA)		Sequence analysis tools: ProtParam, ProtScale, Compute pI/Mw, PeptideMass, PeptideCutter, Dotlet (Java)
	ScanProsite, MotifScan		Submit a homology modeling request to SWISS-MODEL
	NPSA Sequence analysis tools