title: Crystallization of the dI component of transhydrogenase, a proton-translocating membrane protein.
abstract: Nicotinamide nucleotide transhydrogenase couples the exchange of a hydride-ion equivalent between NAD(H) and NADP(H) to the translocation of protons across an energy-transducing membrane. Peripheral components of 380 and 200 residues bind NAD(H) (dI) and NADP(H) (dIII), respectively, while a third component forms a membrane-spanning region (dII). The NAD(H)-binding component dI of Rhodospirillum rubrum transhydrogenase has been crystallized in a form which diffracts to beyond 3.0 A resolution and is in space group P2 or P2(1), with unit-cell parameters a = 69.3, b = 117.8, c = 106.6 A, beta = 107.2 degrees and two dimers in the asymmetric unit. The sequence of the dI component is similar to that of alanine dehydrogenase. A full structure determination will lead to important information on the mode of action of this proton pump and will permit the comparison of the structure-function relationships of dI with those of alanine dehydrogenase.
authors.affiliation: The Krebs Institute, Department of Molecular Biology and Biotechnology, University of Sheffield, Western Bank, Sheffield S10 2TN, England.
authors.forename: S E
authors.initials: SE
authors.lastname: Sedelnikova
authors.forename: J
authors.initials: J
authors.lastname: Burke
authors.forename: P A
authors.initials: PA
authors.lastname: Buckley
authors.forename: D W
authors.initials: DW
authors.lastname: Rice
authors.forename: J B
authors.initials: JB
authors.lastname: Jackson
authors.forename: N P
authors.initials: NP
authors.lastname: Cotton
authors.forename: R L
authors.initials: RL
authors.lastname: Grimley
authors.forename: P J
authors.initials: PJ
authors.lastname: Baker
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D001665:Binding Sites; D003460:Crystallization; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D009250:NADP Transhydrogenases / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D012247:Rhodospirillum rubrum / Q000201:enzymology / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D011994:Recombinant Proteins; D009250:NADP Transhydrogenases