title: Investigation of the role of the cydD gene product in production of a functional cytochrome d oxidase in Escherichia coli.
abstract: The cydD gene is needed for the formation of a functional cytochrome d oxidase in the aerobic respiratory chain of Escherichia coli. In this paper we demonstrate that transcription from a cydA-lacZ gene fusion is not significantly affected in a cydD mutant. This, together with the finding that subunit I of cytochrome d is present in cytoplasmic membranes of a cydD mutant, rules out a role for CydD in the regulation of cytochrome d expression or the assembly of its polypeptides into the membrane. The activity of the haem d-containing catalase HP II was found to be similar in a cydD mutant and the wild-type. Therefore, if CydD has a role in haem d biosynthesis it must be in a unique step only associated with the synthesis of the haem d prosthetic group of cytochrome d.
authors.affiliation: Department of Biology, Imperial College of Science, Technology and Medicine, London, UK.
authors.forename: K J
authors.initials: KJ
authors.lastname: Bebbington
authors.forename: H D
authors.initials: HD
authors.lastname: Williams
mesh_terms: D002374:Catalase / Q000235:genetics / Q000378:metabolism; D003001:Cloning, Molecular; D003573:Cytochrome b Group; D017937:Cytochrome d Group / Q000096:biosynthesis / Q000235:genetics*; D003580:Cytochromes / Q000096:biosynthesis / Q000235:genetics*; D045222:Electron Transport Chain Complex Proteins; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism; D029968:Escherichia coli Proteins; D015870:Gene Expression; D005798:Genes, Bacterial; D006418:Heme / Q000096:biosynthesis; D007763:Lac Operon; D009154:Mutation; D010088:Oxidoreductases / Q000096:biosynthesis / Q000235:genetics*; D014158:Transcription, Genetic
chemical_list: D003573:Cytochrome b Group; D003580:Cytochromes; D045222:Electron Transport Chain Complex Proteins; D029968:Escherichia coli Proteins; D006418:Heme; D017937:Cytochrome d Group; D010088:Oxidoreductases; D002374:Catalase; C040077:cytochrome bd terminal oxidase complex, E coli