title: A MAS NMR study of the bacterial ABC transporter ArtMP.
abstract: ATP-binding cassette (ABC) transport systems facilitate the translocation of substances, like amino acids, across cell membranes energised by ATP hydrolysis. This work describes first structural studies on the ABC transporter ArtMP from Geobacillus stearothermophilus in native lipid environment by magic-angle spinning NMR spectroscopy. The 2D crystals of ArtMP and 3D crystals of isolated ArtP were prepared in different nucleotide-bound or -unbound states. From selectively (13)C,(15)N-labelled ArtP, several sequence-specific assignments were obtained, most of which could be transferred to spectra of ArtMP. Residues Tyr133 and Pro134 protrude directly into the ATP-binding pocket at the interface of the ArtP subunits, and hence, are sensitive monitors for structural changes during nucleotide binding and hydrolysis. Distinct sets of NMR shifts were obtained for ArtP with different phosphorylation states of the ligand. Indications were found for an asymmetric or inhomogeneous state of the ArtP dimer bound with triphosphorylated nucleotides. With this investigation, a model system was established for screening all functional states occurring in one ABC transporter in native lipid environment.
authors.affiliation: NMR-Supported Structural Biology, Leibniz-Institut für Molekulare Pharmakologie, R.-Rössle-Strasse 10, 13125 Berlin, Germany.
authors.forename: Vivien
authors.initials: V
authors.lastname: Lange
authors.forename: Johanna
authors.initials: J
authors.lastname: Becker-Baldus
authors.forename: Britta
authors.initials: B
authors.lastname: Kunert
authors.forename: Barth-Jan
authors.initials: BJ
authors.lastname: van Rossum
authors.forename: Fabio
authors.initials: F
authors.lastname: Casagrande
authors.forename: Andreas
authors.initials: A
authors.lastname: Engel
authors.forename: Yvette
authors.initials: Y
authors.lastname: Roske
authors.forename: Frank M
authors.initials: FM
authors.lastname: Scheffel
authors.forename: Erwin
authors.initials: E
authors.lastname: Schneider
authors.forename: Hartmut
authors.initials: H
authors.lastname: Oschkinat
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000737:chemistry*; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry*; D003460:Crystallization; D001411:Geobacillus stearothermophilus / Q000737:chemistry*; D008055:Lipids / Q000737:chemistry; D008958:Models, Molecular; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular
chemical_list: D018528:ATP-Binding Cassette Transporters; D001426:Bacterial Proteins; D008055:Lipids