Labeling strategies for 13C-detected aligned-sample solid-state NMR of proteins

J Magn Reson. 2009 Dec;201(2):121-30. doi: 10.1016/j.jmr.2009.08.012. Epub 2009 Sep 2.

Abstract

(13)C-detected solid-state NMR experiments have substantially higher sensitivity than the corresponding (15)N-detected experiments on stationary, aligned samples of isotopically labeled proteins. Several methods for tailoring the isotopic labeling are described that result in spatially isolated (13)C sites so that dipole-dipole couplings among the (13)C are minimized, thus eliminating the need for homonuclear (13)C-(13)C decoupling in either indirect or direct dimensions of one- or multi-dimensional NMR experiments that employ (13)C detection. The optimal percentage for random fractional (13)C labeling is between 25% and 35%. Specifically labeled glycerol and glucose can be used at the carbon sources to tailor the isotopic labeling, and the choice depends on the resonances of interest for a particular study. For investigations of the protein backbone, growth of the bacteria on [2-(13)C]-glucose-containing media was found to be most effective.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / analysis*
  • Bacterial Proteins / chemistry*
  • Carbon Isotopes / analysis
  • Carbon Isotopes / chemistry
  • Isotope Labeling / methods
  • Magnetic Resonance Spectroscopy / methods*
  • Phase Transition
  • Powders

Substances

  • Bacterial Proteins
  • Carbon Isotopes
  • Powders