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A0A0B4MRK3 · A0A0B4MRK3_9APIA

  • Protein
    Cytochrome b6
  • Gene
    petB
  • Status
    UniProtKB unreviewed (TrEMBL)
  • Amino acids
  • Protein existence
    Inferred from homology
  • Annotation score
    3/5

Function

function

Component of the cytochrome b6-f complex, which mediates electron transfer between photosystem II (PSII) and photosystem I (PSI), cyclic electron flow around PSI, and state transitions.

Miscellaneous

Heme 1 (or BH or b566) is high-potential and absorbs at about 566 nm, and heme 2 (or BL or b562) is low-potential and absorbs at about 562 nm.

Cofactor

Protein has several cofactor binding sites:
heme b (UniProtKB | Rhea| CHEBI:60344 )

Note: Binds 2 heme b groups non-covalently with two histidine residues as axial ligands.
heme c (UniProtKB | Rhea| CHEBI:61717 )

Note: Binds one heme group covalently by a single cysteine link with no axial amino acid ligand. This heme was named heme ci.

Features

Showing features for binding site.

121520406080100120140160180200
TypeIDPosition(s)Description
Binding site35heme c (UniProtKB | ChEBI); covalent
Binding site86Fe (UniProtKB | ChEBI) of heme b 2 (UniProtKB | ChEBI); axial binding residue
Binding site100Fe (UniProtKB | ChEBI) of heme b 1 (UniProtKB | ChEBI); axial binding residue
Binding site187Fe (UniProtKB | ChEBI) of heme b 2 (UniProtKB | ChEBI); axial binding residue
Binding site202Fe (UniProtKB | ChEBI) of heme b 1 (UniProtKB | ChEBI); axial binding residue

GO annotations

AspectTerm
Cellular Componentchloroplast thylakoid membrane
Molecular Functionelectron transporter, transferring electrons within cytochrome b6/f complex of photosystem II activity
Molecular Functionmetal ion binding
Molecular Functionoxidoreductase activity
Biological Processphotosynthesis
Biological Processrespiratory electron transport chain

Keywords

Names & Taxonomy

Protein names

  • Recommended name
    Cytochrome b6

Gene names

    • Name
      petB
    • ORF names
      WH49_00051

Encoded on

  • Chloroplast

Organism names

  • Taxonomic identifier
  • Organism
  • Strains
    • LCK-1
    • LCK-10
    • LCK-2
    • LCK-3
    • LCK-4
  • Taxonomic lineage
    Eukaryota > Viridiplantae > Streptophyta > Embryophyta > Tracheophyta > Spermatophyta > Magnoliopsida > eudicotyledons > Gunneridae > Pentapetalae > asterids > campanulids > Apiales > Araliaceae > Panax

Accessions

  • Primary accession
    A0A0B4MRK3

Subcellular Location

Membrane
; Multi-pass membrane protein
Plastid, chloroplast thylakoid membrane
; Multi-pass membrane protein

Features

Showing features for transmembrane.

TypeIDPosition(s)Description
Transmembrane32-58Helical
Transmembrane88-106Helical
Transmembrane118-138Helical
Transmembrane184-203Helical

Keywords

Interaction

Subunit

The 4 large subunits of the cytochrome b6-f complex are cytochrome b6, subunit IV (17 kDa polypeptide, PetD), cytochrome f and the Rieske protein, while the 4 small subunits are PetG, PetL, PetM and PetN. The complex functions as a dimer.

Family & Domains

Features

Showing features for domain.

TypeIDPosition(s)Description
Domain4-215Cytochrome b/b6 N-terminal region profile

Sequence similarities

Belongs to the cytochrome b family. PetB subfamily.

Keywords

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Length
    215
  • Mass (Da)
    24,121
  • Last updated
    2015-04-01 v1
  • MD5 Checksum
    B0B2F38A7075214D02E815294CCBD8DF
MSKVYDWFEERLEIQAIADDITSKYVPPHVNIFYCLGGITLTCFLVQVATGFAMTFYYRPTVTDAFASVQYIMTEANFGWLIRSVHRWSASMMVLMMILHVFRVYLTGGFKKPRELTWVTGVVLAVLTASFGVTGYSLPRDQIGYWAVKIVTGVPEAIPVIGSPLVELLRGSASVGQSTLTRFYSLHTFVLPLLTAVFMLMHFPMIRKQGISGPL

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
KJ566590
EMBL· GenBank· DDBJ
AIA24357.1
EMBL· GenBank· DDBJ
Genomic DNA
KP036468
EMBL· GenBank· DDBJ
AKB99101.1
EMBL· GenBank· DDBJ
Genomic DNA
KR021381
EMBL· GenBank· DDBJ
AKG26630.1
EMBL· GenBank· DDBJ
Genomic DNA
KT001509
EMBL· GenBank· DDBJ
AKU70806.1
EMBL· GenBank· DDBJ
Genomic DNA
MK408925
EMBL· GenBank· DDBJ
QDI96002.1
EMBL· GenBank· DDBJ
Genomic DNA
MK408927
EMBL· GenBank· DDBJ
QDI96176.1
EMBL· GenBank· DDBJ
Genomic DNA
MK408928
EMBL· GenBank· DDBJ
QDI96263.1
EMBL· GenBank· DDBJ
Genomic DNA
MK408931
EMBL· GenBank· DDBJ
QDI96526.1
EMBL· GenBank· DDBJ
Genomic DNA
MK408937
EMBL· GenBank· DDBJ
QDI97051.1
EMBL· GenBank· DDBJ
Genomic DNA
MK408945
EMBL· GenBank· DDBJ
QDI97750.1
EMBL· GenBank· DDBJ
Genomic DNA
MK408946
EMBL· GenBank· DDBJ
QDI97837.1
EMBL· GenBank· DDBJ
Genomic DNA
MK408954
EMBL· GenBank· DDBJ
QDI98538.1
EMBL· GenBank· DDBJ
Genomic DNA
MK408955
EMBL· GenBank· DDBJ
QDI98625.1
EMBL· GenBank· DDBJ
Genomic DNA

Genome annotation databases

Similar Proteins

Disclaimer

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