title: In vitro formation of a c-type cytochrome.
abstract: C-type cytochromes are essential for almost all organisms; they are characterized by the covalent attachment of heme to protein through two thioether bonds to a Cys-Xaa-Xaa-Cys-His peptide motif. Here we show, contrary to opinion of 30 years standing, that a c-type cytochrome can form from heme and apoprotein in vitro under mild conditions and in the absence of any biosynthesis apparatus. This reaction occurs provided formation of a disulfide bond within the Cys-Xaa-Xaa-Cys-His motif is avoided. There are important implications for understanding in vivo cytochrome c assembly.
authors.affiliation: Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, United Kingdom.
authors.forename: Oliver
authors.initials: O
authors.lastname: Daltrop
authors.forename: James W A
authors.initials: JW
authors.lastname: Allen
authors.forename: Anthony C
authors.initials: AC
authors.lastname: Willis
authors.forename: Stuart J
authors.initials: SJ
authors.lastname: Ferguson
mesh_terms: D000595:Amino Acid Sequence; D001051:Apoenzymes / Q000737:chemistry / Q000378:metabolism; D001419:Bacteria / Q000201:enzymology; D002942:Circular Dichroism; D003574:Cytochrome c Group / Q000737:chemistry* / Q000378:metabolism; D006418:Heme / Q000378:metabolism; D011487:Protein Conformation; D013053:Spectrophotometry
chemical_list: D001051:Apoenzymes; D003574:Cytochrome c Group; D006418:Heme