NMR “Crystallography” for Uniformly (13C, 15N)‐Labeled Oriented Membrane Proteins

Abstract

In oriented‐sample (OS) solid‐state NMR of membrane proteins, the angular‐dependent dipolar couplings and chemical shifts provide a direct input for structure calculations. However, so far only 1H–15N dipolar couplings and 15N chemical shifts have been routinely assessed in oriented 15N‐labeled samples. The main obstacle for extending this technique to membrane proteins of arbitrary topology has remained in the lack of additional experimental restraints. We have developed a new experimental triple‐resonance NMR technique, which was applied to uniformly doubly (15N, 13C)‐labeled Pf1 coat protein in magnetically aligned DMPC/DHPC bicelles. The previously inaccessible 1Hα–13Cα dipolar couplings have been measured, which make it possible to determine the torsion angles between the peptide planes without assuming α‐helical structure a priori. The fitting of three angular restraints per peptide plane and filtering by Rosetta scoring functions has yielded a consensus α‐helical transmembrane structure for Pf1 protein.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jan 23, 2020
Source ID
10.1002/ange.201915110

Entities

People

  • Alexander A Nevzorov
  • Emmanuel O. Awosanya
  • Joel Lapin

Organizations

  • Army Research Office
  • Division of Molecular & Cellular Biosciences
  • North Carolina State University

Tags

Readers

  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Molecular and Cellular Biochemistry
  • Quantum spin resonance or Electron Paramagnetic Resonance spectroscopy.