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The interplay between the disulfide bond formation pathway and cytochrome c maturation in Escherichia coli.

ABSTRACT: Heme attachment to c-type cytochromes in bacteria requires cysteine thiols in the CXXCH motif of the protein. The involvement of the periplasmic disulfide generation system in this process remains unclear. We undertake a systematic evaluation of the role of DsbA and DsbD in cytochrome c biogenesis in Escherichia coli and show unequivocally that DsbA is not essential for holocytochrome production under aerobic or anaerobic conditions. We also prove that DsbD is important but not essential for maturation of c-type cytochromes. We discuss the findings in the context of a model in which heme attachment to, and oxidation of, the apocytochrome are competing processes.

SUBMITTER: Mavridou DA

PROVIDER: S-EPMC3420020 | biostudies-literature | 2012 Jun

REPOSITORIES: biostudies-literature

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The interplay between the disulfide bond formation pathway and cytochrome c maturation in Escherichia coli.

Mavridou Despoina A I DA Ferguson Stuart J SJ Stevens Julie M JM

FEBS letters 20120505 12

Heme attachment to c-type cytochromes in bacteria requires cysteine thiols in the CXXCH motif of the protein. The involvement of the periplasmic disulfide generation system in this process remains unclear. We undertake a systematic evaluation of the role of DsbA and DsbD in cytochrome c biogenesis in Escherichia coli and show unequivocally that DsbA is not essential for holocytochrome production under aerobic or anaerobic conditions. We also prove that DsbD is important but not essential for mat ...[more]

PMID: 22569094

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