title: Cytochrome oxidase from thermophilic bacterium PS3 contains a fourth protein subunit.
abstract: Monoclonal antibodies prepared against subunits II and IV of beef heart cytochrome oxidase were found to cross-react with thermophilic bacterial PS3 oxidase. Each individual antibody affects the enzymatic activity. "Western" blot analyses showed that subunit II antibodies of beef heart recognized subunit II of PS3 and subunit IV antibody likewise recognized a fourth protein subunit on slab gels. This fourth subunit previously thought to be a contaminant or a degradation product has a molecular weight of about 10,500 on SDS-gels, and appears to exist in stoichiometric amount. We have extracted this subunit from slab gels and compared its amino acid composition with that of subunit III.
authors.affiliation: Department of Biology, Syracuse University, NY 13244.
authors.forename: W Z
authors.initials: WZ
authors.lastname: Gai
authors.forename: S M
authors.initials: SM
authors.lastname: Sun
authors.forename: N
authors.initials: N
authors.lastname: Sone
authors.forename: S H
authors.initials: SH
authors.lastname: Chan
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D000911:Antibodies, Monoclonal; D001419:Bacteria / Q000201:enzymology*; D002417:Cattle; D003429:Cross Reactions; D003576:Electron Transport Complex IV / Q000276:immunology / Q000302:isolation & purification*; D004797:Enzyme-Linked Immunosorbent Assay; D006358:Hot Temperature; D046911:Macromolecular Substances; D008970:Molecular Weight; D009206:Myocardium / Q000201:enzymology
chemical_list: D000596:Amino Acids; D000911:Antibodies, Monoclonal; D046911:Macromolecular Substances; D003576:Electron Transport Complex IV