Q8PHC8 · CYSI_XANAC

Function

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.

Catalytic activity

Cofactor

Protein has several cofactor binding sites:
siroheme (UniProtKB | Rhea| CHEBI:60052 )

Note: Binds 1 siroheme per subunit.
[4Fe-4S] cluster (UniProtKB | Rhea| CHEBI:49883 )

Note: Binds 1 [4Fe-4S] cluster per subunit.

Pathway

Sulfur metabolism; hydrogen sulfide biosynthesis; hydrogen sulfide from sulfite (NADPH route): step 1/1.

Features

Showing features for binding site.

TypeIDPosition(s)Description
Binding site425[4Fe-4S] cluster (UniProtKB | ChEBI)
Binding site431[4Fe-4S] cluster (UniProtKB | ChEBI)
Binding site470[4Fe-4S] cluster (UniProtKB | ChEBI)
Binding site474[4Fe-4S] cluster (UniProtKB | ChEBI)
Binding site474Fe (UniProtKB | ChEBI) of siroheme (UniProtKB | ChEBI); axial binding residue

GO annotations

AspectTerm
Cellular Componentsulfite reductase complex (NADPH)
Molecular Function4 iron, 4 sulfur cluster binding
Molecular Functionheme binding
Molecular Functionmetal ion binding
Molecular FunctionNADP binding
Molecular Functionsulfite reductase (ferredoxin) activity
Molecular Functionsulfite reductase (NADPH) activity
Biological Processcysteine biosynthetic process
Biological Processhydrogen sulfide biosynthetic process
Biological Processsulfate assimilation

Keywords

Enzyme and pathway databases

Names & Taxonomy

Protein names

  • Recommended name
    Sulfite reductase [NADPH] hemoprotein beta-component
  • EC number
  • Short names
    SiR-HP
    ; SiRHP

Gene names

    • Name
      cysI
    • Ordered locus names
      XAC3331

Organism names

Accessions

  • Primary accession
    Q8PHC8

Proteomes

Subcellular Location

PTM/Processing

Features

Showing features for chain.

TypeIDPosition(s)Description
ChainPRO_00003885271-568Sulfite reductase [NADPH] hemoprotein beta-component

Interaction

Subunit

Alpha8-beta8. The alpha component is a flavoprotein, the beta component is a hemoprotein.

Structure

Family & Domains

Sequence similarities

Belongs to the nitrite and sulfite reductase 4Fe-4S domain family.

Phylogenomic databases

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Length
    568
  • Mass (Da)
    62,418
  • Last updated
    2002-10-01 v1
  • Checksum
    4E86EDBFF11AE961
MSHSVEDIKSESRRLRGSLEQSLADAVTGALREDDQTLIKYHGSYQQDDRDIRDERRRQKLEPAYQFMIRTRTPGGVITPTQWLALDGIATRYANHSLRITTRQAFQFHGVIKRELKATMQAINATLIDTLAACGDVNRNVQVAANPLLSQAHATLYADAARVSEHLLPNTRAYYEIWLDEERVSGSGSEDEPIYGERYLPRKFKIGFAAPPLNDVDVFANDLGFIAILRDGQLLGYNVSIGGGMGASHGDAETWPRVANVIGFVTREQLLDIATAVVTTQRDFGNRAVRKRARFKYTIDDHGLDTIVAEIARRAGFALQPAQPFAFDHNGDRYGWVEGEDGLWHLTLSLPAGRIADTDTAAHLSGLRAIAQLNVGEFRMTPNQNLVIAGVLASERARVDALVAHYGLDAGNQSATALARGAMACVALPTCGLAMAEAERYLPDFGAALQPLLQQHGLAETPIVLRLSGCPNGCSRPYLAEIALVGKAPGRYNLMLGGDRRGQRLNTLYRENITEPEILAALEPLLARYAAERDHANDEGFGDFLHRAGVIALPPYPTHRRLDLELLA

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
AE008923
EMBL· GenBank· DDBJ
AAM38174.1
EMBL· GenBank· DDBJ
Genomic DNA

Genome annotation databases

Similar Proteins

Disclaimer

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