ArticleProceedings of the National Academy of Sciences of the United States of America2009
CcsBA is a cytochrome c synthetase that also functions in heme transport.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2009. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 52 papers.
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52 citing papers in PubMed, 73 citations in OpenAlex.
- Inhibitors of cytochromemBio · 2026Article
- Analysis of putative heme ligands in the System I bacterial cytochromeMicrobiology spectrum · 2026Article
- From genes to function: regulation, maturation, and evolution of cytochromeApplied and environmental microbiology · 2025Review
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- Structural Insights into Mechanisms Underlying Mitochondrial and Bacterial Cytochrome c Synthases.Biomolecules · 2024Article
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- Helicobacter pylori and Campylobacter jejuni bacterial holocytochrome c synthase structure-function analysis reveals conservation of heme binding.Communications biology · 2024Article
- Recombinant Biogenesis and Analysis of Cytochrome c Species.Methods in molecular biology (Clifton, N.J.) · 2024Article
- Structural basis of membrane machines that traffick and attach heme to cytochromes.The Journal of biological chemistry · 2023Article
- Article
- Structures of the CcmABCD heme release complex at multiple states.Nature communications · 2022Article
- Cryo-EM of CcsBA reveals the basis for cytochrome c biogenesis and heme transport.Nature chemical biology · 2022Article
- Handling heme with care.Nature chemical biology · 2021Article
- Architecture of the membrane-bound cytochrome c heme lyase CcmF.Nature chemical biology · 2021Article
- In vitro reconstitution reveals major differences between human and bacterial cytochrome c synthases.eLife · 2021Article
- Article
- Article
- Structurally Mapping Endogenous Heme in the CcmCDE Membrane Complex for Cytochrome c Biogenesis.Journal of molecular biology · 2018Article
- Maturation of PlastidFrontiers in plant science · 2017Review
- Comparative Analyses of Transport Proteins Encoded within the Genomes of Bdellovibrio bacteriovorus HD100 and Bdellovibrio exovorus JSS.Journal of molecular microbiology and biotechnology · 2017Article
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2 authors at 2 institutions in 1 country.
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Abstract
Little is known about trafficking of heme from its sites of synthesis to sites of heme-protein assembly. We describe an integral membrane protein that allows trapping of endogenous heme to elucidate trafficking mechanisms. We show that CcsBA, a representative of a superfamily of integral membrane proteins involved in cytochrome c biosynthesis, exports and protects heme from oxidation. CcsBA has 10 transmembrane domains (TMDs) and reconstitutes cytochrome c synthesis in the Escherichia coli periplasm; thus, CcsBA is a cytochrome c synthetase. Purified CcsBA contains heme in an "external heme binding domain" for which two external histidines are shown to serve as axial ligands that protect the heme iron from oxidation. This is likely the active site of the synthetase. Furthermore, two conserved histidines in TMDs are required for heme to travel to the external heme binding domain. Remarkably, the function of CcsBA with mutations in these TMD histidines is corrected by exogenous imidazole, a result analogous to correction of heme binding by myoglobin when its proximal histidine is mutated. These data suggest that CcsBA has a heme binding site within the bilayer and that CcsBA is a heme channel.
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