Automated NMR determination of protein backbone dihedral angles from cross-correlated spin relaxation.
The simultaneous interpretation of a suite of dipole-dipole and dipole-CSA cross-correlation rates involving the backbone nuclei 13Calpha, 1Halpha, 13CO, 15N and 1HN can be used to resolve the ambiguities associated with each individual cross-correlation rate. The method is based on the transformation of experimental cross-correlation rates via calculated values based on standard peptide plane geometry and solid-state 13CO CSA parameters into a dihedral angle probability surface. Triple resonance NMR experiments with improved sensitivity have been devised for the quantification of relaxation interference between 1Halpha(i)-13Calpha(i)/15N(i)-1HN(i) and 1Halpha(i-1)-13Calpha(i-1)/15N(i)-1HN(i) dipole-dipole mechanisms in 15N, 13C-labeled proteins. The approach is illustrated with an application to 13C, 15N-labeled ubiquitin.
Kloiber
Karin
K
Institute of Organic Chemistry, University of Innsbruck, Austria.
Schüler
Wolfgang
W
Konrat
Robert
R
D002247:Carbon Isotopes / Q000737:chemistry; D009587:Nitrogen Isotopes / Q000737:chemistry; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D011506:Proteins / Q000737:chemistry; D013223:Statistics as Topic; D025801:Ubiquitin / Q000737:chemistry*
D002247:Carbon Isotopes; D009587:Nitrogen Isotopes; D011506:Proteins; D025801:Ubiquitin