title: Subunit II of cytochrome c oxidase from Paracoccus denitrificans. DNA sequence, gene expression and the protein.
abstract: Cytochrome c oxidase from the bacterium Paracoccus denitrificans, while being related to the mitochondrial enzyme in many ways, consists of only two to three different subunits. For the identification of its genes, a Paracoccus DNA library was constructed and screened with specific antibodies for expression of cloned inserts in E. coli. A positive clone expressing immunoreactive products in the molecular mass region of authentic subunit II revealed a high homology of its DNA-deduced amino acid sequence with subunit II sequences of the mitochondrial oxidases; several typical features, such as the transmembrane folding pattern and the presumed copper-binding site, are highly conserved between prokaryotic and mitochondrial polypeptides. A comparison with peptide sequencing data of the purified subunit established the presence of a characteristic N-terminal extension as well as a longer C terminus in the initial translation product of the Paracoccus subunit; by mass spectroscopy, the first N-terminally blocked residue of the mature polypeptide was identified as a pyroglutamate. No code abnormalities, but a highly specific codon usage were observed; no evidence for a localization of the subunit I gene directly adjacent to this gene has been obtained.
authors.affiliation: Institute of Biochemistry, Medical University of Lübeck, Federal Republic of Germany.
authors.forename: P
authors.initials: P
authors.lastname: Steinrücke
authors.forename: G C
authors.initials: GC
authors.lastname: Steffens
authors.forename: G
authors.initials: G
authors.lastname: Panskus
authors.forename: G
authors.initials: G
authors.lastname: Buse
authors.forename: B
authors.initials: B
authors.lastname: Ludwig
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D004262:DNA Restriction Enzymes; D003576:Electron Transport Complex IV / Q000235:genetics*; D005796:Genes; D005798:Genes, Bacterial; D006801:Humans; D008969:Molecular Sequence Data; D010231:Paracoccus denitrificans / Q000201:enzymology / Q000235:genetics*; D010446:Peptide Fragments / Q000032:analysis; D012689:Sequence Homology, Nucleic Acid; D013045:Species Specificity; D014158:Transcription, Genetic
chemical_list: D010446:Peptide Fragments; D003576:Electron Transport Complex IV; D004262:DNA Restriction Enzymes