title: Structure and function of the C-terminal domain of MrpA in the Bacillus subtilis Mrp-antiporter complex--the evolutionary progenitor of the long horizontal helix in complex I.
abstract: MrpA and MrpD are homologous to NuoL, NuoM and NuoN in complex I over the first 14 transmembrane helices. In this work, the C-terminal domain of MrpA, outside this conserved area, was investigated. The transmembrane orientation was found to correspond to that of NuoJ in complex I. We have previously demonstrated that the subunit NuoK is homologous to MrpC. The function of the MrpA C-terminus was tested by expression in a previously used Bacillus subtilis model system. At neutral pH, the truncated MrpA still worked, but at pH 8.4, where Mrp-complex formation is needed for function, the C-terminal domain of MrpA was absolutely required.
authors.affiliation: Department of Biochemistry and Structural Biology, Center for Molecular Protein Science, Lund University, PO Box 124, S-221 00 Lund, Sweden.
authors.forename: Egle
authors.initials: E
authors.lastname: Virzintiene
authors.forename: Vamsi K
authors.initials: VK
authors.lastname: Moparthi
authors.forename: Yusra
authors.initials: Y
authors.lastname: Al-Eryani
authors.forename: Leonard
authors.initials: L
authors.lastname: Shumbe
authors.forename: Kamil
authors.initials: K
authors.lastname: Górecki
authors.forename: Cecilia
authors.initials: C
authors.lastname: Hägerhäll
mesh_terms: D001412:Bacillus subtilis / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D017434:Protein Structure, Tertiary
chemical_list: D001426:Bacterial Proteins
keywords: Complex I; Cytochrome c; Mrp-antiporter complex; MrpA; NuoJ; NuoL