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Q00471 (CYB6_CHLRE) Reviewed, UniProtKB/Swiss-Prot

Last modified February 19, 2014. Version 104. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (2) | Third-party data text xml rdf/xml gff fasta
to top of pageNames·Attributes·General annotation·Ontologies·Sequence annotation·Sequences·References·Cross-refs·Entry info·DocumentsCustomize order

Names and origin

Protein namesRecommended name:
Cytochrome b6
Gene names
Name:petB
Encoded onPlastid; Chloroplast
OrganismChlamydomonas reinhardtii (Chlamydomonas smithii) [Reference proteome]
Taxonomic identifier3055 [NCBI]
Taxonomic lineageEukaryotaViridiplantaeChlorophytaChlorophyceaeChlamydomonadalesChlamydomonadaceaeChlamydomonas

Protein attributes

Sequence length215 AA.
Sequence statusComplete.
Protein existenceEvidence at protein level

General annotation (Comments)

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. HAMAP-Rule MF_00633

Cofactor

Binds 2 heme groups. One heme group is bound covalently by a single cysteine link, the other one non-covalently. Ref.7

Subunit structure

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.

Subcellular location

Plastidchloroplast thylakoid membrane; Multi-pass membrane protein HAMAP-Rule MF_00633.

Post-translational modification

The N-terminus is blocked. HAMAP-Rule MF_00633

Miscellaneous

Creation by mutagenesis of a Pro residue at position 204 (a codon that is known to be RNA edited to a Leu codon in tobacco and maize) leads to assembly defective mutants, indicating that the Leu-204 is essential for proper assembly of the cytochrome b6-f complex. This is probably due to lack of assembly of apocytochrome b6 with one of its heme groups.

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 By similarity.

Sequence similarities

Belongs to the cytochrome b family. PetB subfamily.

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Chain1 – 215215Cytochrome b6 HAMAP-Rule MF_00633
PRO_0000061787

Regions

Transmembrane32 – 5221Helical; Potential
Transmembrane90 – 11021Helical; Potential
Transmembrane116 – 13621Helical; Potential
Transmembrane186 – 20621Helical; Potential

Sites

Metal binding861Iron (heme 2 axial ligand)
Metal binding1001Iron (heme 1 axial ligand)
Metal binding1871Iron (heme 2 axial ligand)
Metal binding2021Iron (heme 1 axial ligand)
Binding site351Heme 1 (covalent; via 1 link)

Experimental info

Mutagenesis2041L → P: Leads to defective cytochrome b6-f complex assembly, probably due to lack of heme assembly. Ref.6

Secondary structure

............................ 215
Helix Strand Turn

Details...

Sequences

Sequence LengthMass (Da)Tools
Q00471 [UniParc].

Last modified December 1, 1992. Version 1.
Checksum: E025FB9ED2ED78B4

FASTA21524,165
        10         20         30         40         50         60 
MSKVYDWFEE RLEIQAIADD ITSKYVPPHV NIFYCIGGIT FTCFLVQVAT GFAMTFYYRP 

        70         80         90        100        110        120 
TVAEAFASVQ YIMTDVNFGW LIRSIHRWSA SMMVLMMVLH VFRVYLTGGF KRPRELTWVT 

       130        140        150        160        170        180 
GVIMAVCTVS FGVTGYSLPW DQVGYWAVKI VTGVPDAIPG VGGFIVELLR GGVGVGQATL 

       190        200        210 
TRFYSLHTFV LPLLTAVFML MHFLMIRKQG ISGPL 

« Hide

References

« Hide 'large scale' references
[1]"Nucleotide sequences of the continuous and separated petA, petB and petD chloroplast genes in Chlamydomonas reinhardtii."
Bueschlen S., Choquet Y., Kuras R., Wollman F.A.
FEBS Lett. 284:257-262(1991) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
Strain: 137c / CC-125.
[2]"Nucleotide sequence of the frxC, petB and trnL genes in the chloroplast genome of Chlamydomonas reinhardtii."
Huang C., Liu X.-Q.
Plant Mol. Biol. 18:985-988(1992) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[3]"Nucleotide diversity of the Chlamydomonas reinhardtii plastid genome: addressing the mutational-hazard hypothesis."
Smith D.R., Lee R.W.
BMC Evol. Biol. 9:120-120(2009) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
Strain: CC-503.
[4]"The Chlamydomonas reinhardtii plastid chromosome: islands of genes in a sea of repeats."
Maul J.E., Lilly J.W., Cui L., dePamphilis C.W., Miller W., Harris E.H., Stern D.B.
Plant Cell 14:2659-2679(2002) [PubMed] [Europe PMC] [Abstract]
Cited for: IDENTIFICATION, COMPLETE PLASTID GENOME.
[5]"Purification and characterization of the cytochrome b6 f complex from Chlamydomonas reinhardtii."
Pierre Y., Breyton C., Kramer D., Popot J.-L.
J. Biol. Chem. 270:29342-29349(1995) [PubMed] [Europe PMC] [Abstract]
Cited for: CHARACTERIZATION.
Strain: WT12.
[6]"Mutations of cytochrome b6 in Chlamydomonas reinhardtii disclose the functional significance for a proline to leucine conversion by petB editing in maize and tobacco."
Zito F., Kuras R., Choquet Y., Koessel H., Wollman F.-A.
Plant Mol. Biol. 33:79-86(1997) [PubMed] [Europe PMC] [Abstract]
Cited for: MUTAGENESIS OF LEU-204.
Strain: 137c / CC-125.
[7]"Biochemical and spectroscopic characterization of the covalent binding of heme to cytochrome b6."
de Vitry C., Desbois A., Redeker V., Zito F., Wollman F.A.
Biochemistry 43:3956-3968(2004) [PubMed] [Europe PMC] [Abstract]
Cited for: HEME-BINDING.
[8]"An atypical haem in the cytochrome b(6)f complex."
Stroebel D., Choquet Y., Popot J.-L., Picot D.
Nature 426:413-418(2003) [PubMed] [Europe PMC] [Abstract]
Cited for: X-RAY CRYSTALLOGRAPHY (3.1 ANGSTROMS).

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
X62905 Genomic DNA. Translation: CAA44690.1.
X72918 Genomic DNA. Translation: CAA51423.1.
FJ423446 Genomic DNA. Translation: ACJ50098.1.
BK000554 Genomic DNA. Translation: DAA00911.1.
PIRS21253.
RefSeqNP_958365.1. NC_005353.1.

3D structure databases

PDBe
RCSB PDB
PDBj
EntryMethodResolution (Å)ChainPositionsPDBsum
1Q90X-ray3.10B1-215[»]
ProteinModelPortalQ00471.
SMRQ00471. Positions 4-215.
ModBaseSearch...
MobiDBSearch...

Protein-protein interaction databases

DIPDIP-58593N.

Proteomic databases

PRIDEQ00471.

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Genome annotation databases

EnsemblPlantsDAA00911; DAA00911; DAA00911.
GeneID2717017.
KEGGcre:ChreCp008.

Phylogenomic databases

KOK02635.
ProtClustDBCHL00070.

Enzyme and pathway databases

BioCycCHLAMY:CHRECP008-MONOMER.
MetaCyc:CHRECP008-MONOMER.

Family and domain databases

Gene3D1.20.810.10. 1 hit.
HAMAPMF_00633. Cytb6_f_cytb6.
InterProIPR016175. Cyt_b/b6.
IPR005797. Cyt_b/b6_N.
IPR023530. Cyt_B6_PetB.
IPR027387. Cytb/b6-like.
IPR016174. Di-haem_cyt_TM.
[Graphical view]
PANTHERPTHR19271:SF0. PTHR19271:SF0. 1 hit.
PfamPF13631. Cytochrom_B_N_2. 1 hit.
[Graphical view]
PIRSFPIRSF000032. Cytochrome_b6. 1 hit.
SUPFAMSSF81342. SSF81342. 1 hit.
PROSITEPS51002. CYTB_NTER. 1 hit.
[Graphical view]
ProtoNetSearch...

Other

EvolutionaryTraceQ00471.

Entry information

Entry nameCYB6_CHLRE
AccessionPrimary (citable) accession number: Q00471
Secondary accession number(s): B7U1F1
Entry history
Integrated into UniProtKB/Swiss-Prot: December 1, 1992
Last sequence update: December 1, 1992
Last modified: February 19, 2014
This is version 104 of the entry and version 1 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programPlant Protein Annotation Program

Relevant documents

SIMILARITY comments

Index of protein domains and families

PDB cross-references

Index of Protein Data Bank (PDB) cross-references