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P83791 (CYB6_MASLA) Reviewed, UniProtKB/Swiss-Prot

Last modified May 29, 2013. Version 64. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (2) | Third-party data text xml rdf/xml gff fasta
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Names and origin

Protein namesRecommended name:
Cytochrome b6
Gene names
Name:petB
OrganismMastigocladus laminosus (Fischerella sp.)
Taxonomic identifier83541 [NCBI]
Taxonomic lineageBacteria › Cyanobacteria › Stigonematales › Mastigocladus

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.1

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

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

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 By similarity. HAMAP-Rule MF_00633

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_0000061827

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)

Secondary structure

1 ............................... 215
Helix Strand Turn

Details...

Sequences

Sequence LengthMass (Da)Tools
P83791 [UniParc].

Last modified March 15, 2004. Version 1.
Checksum: 4FDCD9336CD31642

FASTA21524,227
        10         20         30         40         50         60 
MANVYDWFQE RLEIQALADD VTSKYVPPHV NIFYCLGGIT LTCFLIQFAT GFAMTFYYKP 

        70         80         90        100        110        120 
TVTEAYASVQ YIMNEVSFGW LIRSIHRWSA SMMVLMMILH VFRVYLTGGF KKPRELTWIS 

       130        140        150        160        170        180 
GVILAVITVS FGVTGYSLPW DQVGYWAVKI VSGVPEAIPV VGVLISDLLR GGSSVGQATL 

       190        200        210 
TRYYSAHTFV LPWLIAVFML LHFLMIRKQG ISGPL

« Hide

References

[1]"Full subunit coverage liquid chromatography electrospray ionization mass spectrometry (LCMS+) of an oligomeric membrane protein: cytochrome b(6)f complex from spinach and the cyanobacterium Mastigocladus laminosus."
Whitelegge J.P., Zhang H., Aguilera R., Taylor R.M., Cramer W.A.
Mol. Cell. Proteomics 1:816-827(2002) [PubMed] [Europe PMC] [Abstract]
Cited for: HEME-BINDING.
[2]"Structure of the cytochrome b6f complex of oxygenic photosynthesis: tuning the cavity."
Kurisu G., Zhang H., Smith J.L., Cramer W.A.
Science 302:1009-1014(2003) [PubMed] [Europe PMC] [Abstract]
Cited for: X-RAY CRYSTALLOGRAPHY (3.0 ANGSTROMS), METAL-BINDING SITES.
+Additional computationally mapped references.

Cross-references

3D structure databases

PDBe
RCSB PDB
PDBj
EntryMethodResolution (Å)ChainPositionsPDBsum
1VF5X-ray3.00A/N1-215[»]
2D2CX-ray3.80A/N1-215[»]
2E74X-ray3.00A1-215[»]
2E75X-ray3.55A1-215[»]
2E76X-ray3.41A1-215[»]
4H0LX-ray3.25A1-215[»]
4H13X-ray3.07A1-215[»]
ProteinModelPortalP83791.
SMRP83791. Positions 1-215.
ModBaseSearch...

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

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. PTHR19271. 1 hit.
PfamPF13631. Cytochrom_B_N_2. 1 hit.
[Graphical view]
PIRSFPIRSF000032. Cytochrome_b6. 1 hit.
SUPFAMSSF81342. Transmembr_di-haem_cytochrome. 1 hit.
PROSITEPS51002. CYTB_NTER. 1 hit.
[Graphical view]
ProtoNetSearch...

Other

EvolutionaryTraceP83791.

Entry information

Entry nameCYB6_MASLA
AccessionPrimary (citable) accession number: P83791
Entry history
Integrated into UniProtKB/Swiss-Prot: April 13, 2004
Last sequence update: March 15, 2004
Last modified: May 29, 2013
This is version 64 of the entry and version 1 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programProkaryotic Protein Annotation Program

Relevant documents

PDB cross-references

Index of Protein Data Bank (PDB) cross-references

SIMILARITY comments

Index of protein domains and families

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