tailieunhanh - Báo cáo khoa học: Order within a mosaic distribution of mitochondrial c-type cytochrome biogenesis systems?

Mitochondrial cytochromescandc1 are present in all eukaryotes that use oxygen as the terminal electron acceptor in the respiratory chain. Matura-tion of c-type cytochromes requires covalent attachment of the heme cofac-tor to the protein, and there are at least five distinct biogenesis systems that catalyze this post-translational modification in different organisms and organelles. | IFEBS Journal REVIEW ARTICLE Order within a mosaic distribution of mitochondrial c-type cytochrome biogenesis systems James W. A. Allen1 Andrew P. Jackson2 Daniel J. Rigden3 Antony C. Willis4 Stuart J. Ferguson1 and Michael L. Ginger5 6 1 Department of Biochemistry University of Oxford UK 2 Wellcome Trust Sanger Institute Hinxton Cambridgeshire UK 3 Schoolof BiologicalSciences University of Liverpool UK 4 MRC Immunochemistry Unit Department of Biochemistry University of Oxford UK 5 Sir William Dunn Schoolof Pathology University of Oxford UK 6 Department of BiologicalSciences Lancaster University UK Keywords bioinformatics Ccm system cytochrome c Diplonema papillatum evolution heme lyase lateral gene transfer mitochondria post-translationalmodification Trypanosoma Correspondence M. Ginger Department of Biological Sciences Lancaster University Lancaster LA1 4YQ UK Fax 44 1524 593192 Tel 44 1524 593922 E-mail Received 7 February 2008 revised 3 March 2008 accepted 5 March 2008 doi Mitochondrial cytochromes c and c1 are present in all eukaryotes that use oxygen as the terminal electron acceptor in the respiratory chain. Maturation of c-type cytochromes requires covalent attachment of the heme cofactor to the protein and there are at least five distinct biogenesis systems that catalyze this post-translational modification in different organisms and organelles. In this study we use biochemical data comparative genomic and structural bioinformatics investigations to provide a holistic view of mitochondrial c-type cytochrome biogenesis and its evolution. There are three pathways for mitochondrial c-type cytochrome maturation only one of which is present in prokaryotes. We analyze the evolutionary distribution of these biogenesis systems which include the Ccm system System I and the enzyme heme lyase System III . We conclude that heme lyase evolved once and in many lineages replaced the multicomponent Ccm system .