title: Inter- and intramolecular contacts in a membrane protein/surfactant complex observed by heteronuclear dipole-to-dipole cross-relaxation.
abstract: Heteronuclear dipole-to-dipole cross-relaxation has been applied to exploring intermolecular interactions and intramolecular spatial proximities in a large supramolecular structure comprised of a beta-barrel membrane protein, OmpX, in complex with a polymeric surfactant, amphipol A8-35. The experiments, performed in either the laboratory or the rotating frame, reveal the existence of intermolecular contacts between aromatic amino acids and specific groups of the polymer, in addition to intra-protein dipolar interactions, some of them involving carbonyl carbons. This study opens the perspective of collecting by NMR spectroscopy a new kind of through-space structural information involving aromatic and carbonyl (13)C atoms of large proteins.
authors.affiliation: Laboratoire de Physico-Chimie Moléculaire des Membranes Biologiques, UMR 7099 CNRS/Université Paris-7, IBPC, 13 rue Pierre et Marie Curie, F-75005 Paris, France. laurent.catoire@ibpc.fr
authors.forename: Laurent J
authors.initials: LJ
authors.lastname: Catoire
authors.forename: Manuela
authors.initials: M
authors.lastname: Zoonens
authors.forename: Carine
authors.initials: C
authors.lastname: van Heijenoort
authors.forename: Fabrice
authors.initials: F
authors.lastname: Giusti
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Popot
authors.forename: Eric
authors.initials: E
authors.lastname: Guittet
mesh_terms: D000465:Algorithms; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry*; D001665:Binding Sites; D003198:Computer Simulation; D029968:Escherichia coli Proteins / Q000737:chemistry*; D006867:Hydrolases / Q000737:chemistry*; D008565:Membrane Proteins / Q000737:chemistry*; D008956:Models, Chemical; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D011108:Polymers / Q000737:chemistry*; D011437:Propylamines / Q000737:chemistry*; D011485:Protein Binding; D013501:Surface-Active Agents / Q000737:chemistry*
chemical_list: D001425:Bacterial Outer Membrane Proteins; D029968:Escherichia coli Proteins; D008565:Membrane Proteins; D011108:Polymers; D011437:Propylamines; D013501:Surface-Active Agents; C499017:amphipol A8-35; C482905:OmpX protein, E coli; D006867:Hydrolases