title: The CydDC Family of Transporters and Their Roles in Oxidase Assembly and Homeostasis.
abstract: The CydDC complex of Escherichia coli is a heterodimeric ATP-binding cassette type transporter (ABC transporter) that exports the thiol-containing redox-active molecules cysteine and glutathione. These reductants are thought to aid redox homeostasis of the periplasm, permitting correct disulphide folding of periplasmic and secreted proteins. Loss of CydDC results in the periplasm becoming more oxidising and abolishes the assembly of functional bd-type respiratory oxidases that couple the oxidation of ubiquinol to the reduction of oxygen to water. In addition, CydDC-mediated redox control is important for haem ligation during cytochrome c assembly. Given the diverse roles for CydDC in redox homeostasis, respiratory metabolism and the maturation of virulence factors, this ABC transporter is an intriguing system for researchers interested in both the physiology of redox perturbations and the role of low-molecular-weight thiols during infection.
authors.affiliation: School of Biosciences, University of Kent, Canterbury, United Kingdom.
authors.forename: Louise V
authors.initials: LV
authors.lastname: Holyoake
authors.affiliation: Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield, United Kingdom.
authors.forename: Robert K
authors.initials: RK
authors.lastname: Poole
authors.affiliation: School of Biosciences, University of Kent, Canterbury, United Kingdom. Electronic address: m.shepherd@kent.ac.uk.
authors.forename: Mark
authors.initials: M
authors.lastname: Shepherd
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D003545:Cysteine / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology* / Q000502:physiology*; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D005978:Glutathione / Q000378:metabolism; D006706:Homeostasis; D008954:Models, Biological; D008958:Models, Molecular; D008968:Molecular Conformation; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism; D014451:Ubiquinone / Q000031:analogs & derivatives; D014867:Water / Q000378:metabolism
chemical_list: D018528:ATP-Binding Cassette Transporters; C089838:CydC protein, E coli; C089839:CydD protein, E coli; D029968:Escherichia coli Proteins; D014867:Water; D014451:Ubiquinone; D010088:Oxidoreductases; D005978:Glutathione; D003545:Cysteine; C003741:ubiquinol; D010100:Oxygen
keywords: ABC transporter; Cysteine; Disulphide; Glutathione; Redox