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Cytochrome c biogenesis System I.

ABSTRACT: Cytochromes c are widespread respiratory proteins characterized by the covalent attachment of heme. The formation of c-type cytochromes requires, in all but a few exceptional cases, the formation of two thioether bonds between the two cysteine sulfurs in a -CXXCH- motif in the protein and the vinyl groups of heme. The vinyl groups of the heme are not particularly activated and therefore the addition reaction does not physiologically occur spontaneously in cells. There are several diverse post-translational modification systems for forming these bonds. Here, we describe the complex multiprotein cytochrome c maturation (Ccm) system (in Escherichia coli comprising the proteins CcmABCDEFGH), also called System I, that performs the heme attachment. System I is found in plant mitochondria, archaea and many Gram-negative bacteria; the systems found in other organisms and organelles are described elsewhere in this minireview series.

SUBMITTER: Stevens JM

PROVIDER: S-EPMC3601427 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature

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Cytochrome c biogenesis System I.

Stevens Julie M JM Mavridou Despoina A I DA Hamer Rebecca R Kritsiligkou Paraskevi P Goddard Alan D AD Ferguson Stuart J SJ

The FEBS journal 20111020 22

Cytochromes c are widespread respiratory proteins characterized by the covalent attachment of heme. The formation of c-type cytochromes requires, in all but a few exceptional cases, the formation of two thioether bonds between the two cysteine sulfurs in a -CXXCH- motif in the protein and the vinyl groups of heme. The vinyl groups of the heme are not particularly activated and therefore the addition reaction does not physiologically occur spontaneously in cells. There are several diverse post-tr ...[more]

PMID: 21958041

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