title: Full-length Vpu and human CD4(372-433) in phospholipid bilayers as seen by magic angle spinning NMR.
abstract: HIV-1 Vpu and CD4(372-433), a peptide comprising the transmembrane and cytoplasmic domain of human CD4, were recombinantly expressed in Escherichia coli, uniformly labeled with 13C and 15N isotopes, and separately reconstituted into phospholipid bilayers. Highly resolved dipolar cross-polarization (CP)-based solid-state NMR spectra of the two transmembrane proteins were recorded under magic angle sample spinning. Partial assignment of 13C resonances was achieved. Site-specific assignments were obtained for 13 amino acid residues of CD4(372-433) and two Vpu residues. Additional amino acid type-specific assignments were achieved for 10 amino acid spin systems for both CD4(372-433) and Vpu. Further, structural flexibility was probed with different dipolar recoupling techniques, and the correct insertion of the transmembrane domains into the lipid bilayers was confirmed by proton spin diffusion experiments.
authors.forename: Hoa Q
authors.initials: HQ
authors.lastname: Do
authors.forename: Marc
authors.initials: M
authors.lastname: Wittlich
authors.forename: Julian M
authors.initials: JM
authors.lastname: Glück
authors.forename: Luis
authors.initials: L
authors.lastname: Möckel
authors.forename: Dieter
authors.initials: D
authors.lastname: Willbold
authors.forename: Bernd W
authors.initials: BW
authors.lastname: Koenig
authors.forename: Henrike
authors.initials: H
authors.lastname: Heise
mesh_terms: D016880:Anisotropy; D015704:CD4 Antigens / Q000737:chemistry*; D015497:HIV-1 / Q000737:chemistry*; D054298:Human Immunodeficiency Virus Proteins / Q000737:chemistry*; D006801:Humans; D008051:Lipid Bilayers / Q000737:chemistry*; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods; D010446:Peptide Fragments / Q000737:chemistry*; D044367:Phase Transition; D010743:Phospholipids / Q000737:chemistry*; D017434:Protein Structure, Tertiary; D011510:Proteolipids / Q000737:chemistry; D054334:Viral Regulatory and Accessory Proteins / Q000737:chemistry*; D000086082:Viroporin Proteins
chemical_list: D015704:CD4 Antigens; D054298:Human Immunodeficiency Virus Proteins; D008051:Lipid Bilayers; D010446:Peptide Fragments; D010743:Phospholipids; D011510:Proteolipids; D054334:Viral Regulatory and Accessory Proteins; C020485:proteoliposomes; C514859:vpu protein, Human immunodeficiency virus 1; D000086082:Viroporin Proteins