title: Heterologous synthesis of cytochrome c' by Escherichia coli is not dependent on the System I cytochrome c biogenesis machinery.
abstract: Hydrogenophilus thermoluteolus cytochrome c' (PHCP) has typical spectral properties previously observed for other cytochromes c', which comprise Ambler's class II cytochromes c. The PHCP protein sequence (135 amino acids) deduced from the cloned gene is the most homologous (55% identity) to that of cytochrome c' from Allochromatium vinosum (AVCP). These findings indicate that PHCP forms a four-helix bundle structure, similar to AVCP. Strikingly, PHCP with a covalently bound heme was heterologously synthesized in the periplasm of Escherichia coli strains deficient in the DsbD protein, a component of the System I cytochrome c biogenesis machinery. The heterologous synthesis of PHCP by aerobically growing E. coli also occurred without a plasmid carrying the genes for Ccm proteins, other components of the System I machinery. Unlike Ambler's class I general cytochromes c, the synthesis of PHCP is not dependent on the System I machinery and exhibits similarity to that of E. coli periplasmic cytochrome b(562), a 106-residue four-helix bundle.
authors.affiliation: Graduate School of Biosphere Science, Hiroshima University, Higashi-Hiroshima, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Inoue
authors.forename: Satoshi
authors.initials: S
authors.lastname: Wakai
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Nishihara
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Sambongi
mesh_terms: D000595:Amino Acid Sequence; D002841:Chromatiaceae / Q000235:genetics / Q000378:metabolism*; D045304:Cytochromes c / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D045305:Cytochromes c' / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D006418:Heme / Q000378:metabolism*; D043363:Hydrogenophilaceae / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D019897:Periplasm / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid
chemical_list: D045305:Cytochromes c'; D006418:Heme; D045304:Cytochromes c