Cytochrome c oxidase subunit Vb

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Cytochrome c oxidase subunit Vb
PDB 1occ EBI.jpg
Structure of the 13-subunit oxidized cytochrome c oxidase.[1]
Symbol COX5B
Pfam PF01215
InterPro IPR002124
SCOP 1occ
OPM superfamily 4
OPM protein 1v55
CDD cd00924

Cytochrome c oxidase, subunit Vb is a subunit of mitochondrial cytochrome c oxidase complex.

Cytochrome c oxidase (EC is an oligomeric enzymatic complex which is a component of the respiratory chain complex and is involved in the transfer of electrons from cytochrome c to oxygen.[2] In eukaryotes this enzyme complex is located in the mitochondrial inner membrane; in aerobic prokaryotes it is found in the plasma membrane.

In eukaryotes, in addition to the three large subunits, I, II and III, that form the catalytic centre of the enzyme complex, there are a variable number of small polypeptidic subunits. One of these subunits is known as Vb in mammals, V in Dictyostelium discoideum (Slime mold) and IV in yeast, binds a zinc atom. The sequence of subunit Vb is well conserved and includes three conserved cysteines that coordinate the zinc ion.[3][4] Two of these cysteines are clustered in the C-terminal section of the subunit.

Human proteins containing this domain[edit]



  1. ^ Miki K, Sogabe S, Uno A, et al. (May 1994). "Application of an automatic molecular-replacement procedure to crystal structure analysis of cytochrome c2 from Rhodopseudomonas viridis". Acta Crystallogr. D Biol. Crystallogr. 50 (Pt 3): 271–5. doi:10.1107/S0907444993013952. PMID 15299438. 
  2. ^ Capaldi RA, Malatesta F, Darley-Usmar VM (1983). "Structure of cytochrome c oxidase". Biochim. Biophys. Acta 726 (2): 135–148. doi:10.1016/0304-4173(83)90003-4. PMID 6307356. 
  3. ^ Rizzuto R, Sandona D, Brini M, Capaldi RA, Bisson R (1991). "The most conserved nuclear-encoded polypeptide of cytochrome c oxidase is the putative zinc-binding subunit: primary structure of subunit V from the slime mold Dictyostelium discoideum". Biochim. Biophys. Acta 1129 (1): 100–104. doi:10.1016/0167-4781(91)90220-G. PMID 1661610. 
  4. ^ Tsukihara T, Yamaguchi H, Aoyama H, Yamashita E, Tomizaki T, Shinzawa-Itoh K, Nakashima R, Yaono R, Yoshikawa S (1996). "The whole structure of the 13-subunit oxidized cytochrome c oxidase at 2.8 A". Science 272 (5265): 1136–1144. Bibcode:1996Sci...272.1136T. doi:10.1126/science.272.5265.1136. PMID 8638158. 

External links[edit]

This article incorporates text from the public domain Pfam and InterPro IPR002124