Biochemical properties and catalytic domain structure of the CcmH protein from Escherichia coli

Zheng, Xueming; Hong, Jing; Li, Haiyin; Lin, Donghai; Hu, Hongyu

doi:10.1016/j.bbapap.2012.06.017

Cited by 12 publications

(16 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…CcmH has a single TM helix and an unusual three helix-bundle fold distinct from other thioredoxin-like proteins, with a redox active LRCXXCQ motif facing the periplasm [101–103]. Plant CcmH resembles its bacterial counterpart with a membrane anchor and a CXXC motif containing N-terminal domain facing the inter-membrane space.…”

Section: Ccm-system I: Functional Organizationmentioning

confidence: 99%

“…It can interact and reduce an apocyt c mimic peptide in spite of its different active site (VR C TE C G) [104]. E. coli CcmH is a fusion protein with a N-terminal domain corresponding to the redox-active CcmH and a C-terminal portion homologous to CcmI (see below) as found in other organisms, such as R. capsulatus and P. aeruginosa [103, 105]. Both Cys residues of E. coli CcmH are important for Ccm but not essential under all conditions [105, 106].…”

Section: Ccm-system I: Functional Organizationmentioning

confidence: 99%

“…Earlier studies using mutants in vivo , and purified R. capsulatus and E. coli samples in vitro , determined the E m and pKa values of the redox active Cys residues of CcmG, CcmH and apocyts c . These studies proposed a linear dithiol-disulfide cascade, with CcmG reducing CcmH, and CcmH reducing the oxidized apocyts c substrates [92, 103–105, 107–109] (Fig. 4B).…”

Section: Ccm-system I: Functional Organizationmentioning

confidence: 99%

See 2 more Smart Citations

Cytochrome c biogenesis System I: An intricate process catalyzed by a maturase supercomplex?

Verissimo

Daldal

2014

Biochimica et Biophysica Acta (BBA) - Bioenergetics

View full text Add to dashboard Cite

Cytochromes c are ubiquitous heme proteins that are found in most living organisms and are essential for various energy production pathways as well as other cellular processes. Their biosynthesis relies on a complex post-translational process, called cytochrome c biogenesis, responsible for the formation of stereo-specific thioether bonds between the vinyl groups of heme b (protoporphyrin IX-Fe) and the thiol groups of apocytochromes c heme-binding site (C1XXC2H) cysteine residues. In some organisms this process involves up to nine (CcmABCDEFGHI) membrane proteins working together to achieve heme ligation, designated the Cytochrome c maturation (Ccm)-System I. Here, we review recent findings related to the Ccm-System I found in bacteria, archaea and plant mitochondria, with an emphasis on protein interactions between the Ccm components and their substrates (apocytochrome c and heme). We discuss the possibility that the Ccm proteins may form a multi subunit supercomplex (dubbed “Ccm machine”), and based on the currently available data, we present an updated version of a mechanistic model for Ccm.

show abstract

Section: Ccm-system I: Functional Organizationmentioning

confidence: 99%

Section: Ccm-system I: Functional Organizationmentioning

confidence: 99%

Section: Ccm-system I: Functional Organizationmentioning

confidence: 99%

See 1 more Smart Citation

Cytochrome c biogenesis System I: An intricate process catalyzed by a maturase supercomplex?

Verissimo

Daldal

2014

Biochimica et Biophysica Acta (BBA) - Bioenergetics

View full text Add to dashboard Cite

show abstract

“…Surprisingly, the 3D structure of the soluble periplasmic domain of Pa-CcmH revealed that it adopts a peculiar three-helix bundle fold strikingly different from that of canonical thiol-oxidoreductases (Figure 5; PDB: 2HL7; [23]). The N-terminal domain of Ec-CcmH was also shown to have the same 3D structure, although helix-swapping and dimerization have been observed in this case (PDB: 2KW0; [91, 92]). The conserved redox-active motif (LRCPKC) is located in the loop connecting helices 1 and 2; close to the activesite, the crystal structure reveals the presence of a small pocket on the surface of Pa-CcmH surrounded by conserved hydrophobic and polar residues, which could represent the recognition site for the heme-binding motif of apoCyt.…”

Section: System Imentioning

confidence: 87%

Protein Machineries Involved in the Attachment of Heme to Cytochrome c: Protein Structures and Molecular Mechanisms

Travaglini-Allocatelli

2013

Scientifica

View full text Add to dashboard Cite

Cytochromes c (Cyt c) are ubiquitous heme-containing proteins, mainly involved in electron transfer processes, whose structure and functions have been and still are intensely studied. Surprisingly, our understanding of the molecular mechanism whereby the heme group is covalently attached to the apoprotein (apoCyt) in the cell is still largely unknown. This posttranslational process, known as Cyt c biogenesis or Cyt c maturation, ensures the stereospecific formation of the thioether bonds between the heme vinyl groups and the cysteine thiols of the apoCyt heme binding motif. To accomplish this task, prokaryotic and eukaryotic cells have evolved distinctive protein machineries composed of different proteins. In this review, the structural and functional properties of the main maturation apparatuses found in gram-negative and gram-positive bacteria and in the mitochondria of eukaryotic cells will be presented, dissecting the Cyt c maturation process into three functional steps: (i) heme translocation and delivery, (ii) apoCyt thioreductive pathway, and (iii) apoCyt chaperoning and heme ligation. Moreover, current hypotheses and open questions about the molecular mechanisms of each of the three steps will be discussed, with special attention to System I, the maturation apparatus found in gram-negative bacteria.

show abstract

“…The E. coli protein CcmH is expressed as two separate proteins in many other organisms, which are named CcmH (corresponding to the N-terminal domain of E. coli CcmH (N-CcmH)) and CcmI (the equivalent of the C-terminal domain in E. coli (C-CcmH)). N-CcmH has a three-helix bundle structure with a conserved pair of cysteines and has been proposed to have a reductive function (25,26). Interaction between CcmH and apocytochromes has been demonstrated (27) but the route of reductant transfer has not been established.…”

Section: Figmentioning

confidence: 99%

Cytochrome c assembly

2013

View full text Add to dashboard Cite

Cytochromes c are central proteins in energy transduction processes by virtue of their functions in electron transfer in respiration and photosynthesis. They have heme covalently attached to a characteristic CXXCH motif via protein-catalyzed post-translational modification reactions. Several systems with diverse constituent proteins have been identified in different organisms and are required to perform the heme attachment and associated functions. The necessary steps are translocation of the apocytochrome polypeptide to the site of heme attachment, transport and provision of heme to the appropriate compartment, reduction and chaperoning of the apocytochrome, and finally, formation of the thioether bonds between heme and two cysteines in the cytochrome. Here we summarize the established classical models for these processes and present recent progress in our understanding of the individual steps within the different cytochrome c biogenesis systems. V C 2013 IUBMB Life, 65(3): [209][210][211][212][213][214][215][216] 2013

show abstract

Biochemical properties and catalytic domain structure of the CcmH protein from Escherichia coli

Cited by 12 publications

References 35 publications

Cytochrome c biogenesis System I: An intricate process catalyzed by a maturase supercomplex?

Cytochrome c biogenesis System I: An intricate process catalyzed by a maturase supercomplex?

Protein Machineries Involved in the Attachment of Heme to Cytochrome c: Protein Structures and Molecular Mechanisms

Cytochrome c assembly

Contact Info

Product

Resources

About