Simultaneous determination of one- and two-bond scalar and residual dipolar couplings between 13C', 13Calpha and 15N spins in proteins.
Four simple and sensitive HNCO-based methods for measurement of 1J(C'Calpha), 1J(NCalpha) and 2J(NCalpha) coupling constants in protein main chains are presented. Three of these experiments enable the simultaneous measurement of 1J(C'Calpha), 1J(NCalpha) and 2J(NCalpha) couplings. Exploitation of the E.COSY principle provides excellent dispersion of cross peaks in the resulting 3D spectra. The couplings can be retrieved with good accuracy from peak-to-peak separations. Karplus parameterizations are provided for 1J(NCalpha) and 2J(NCalpha), obtained from a nearly complete set of couplings of human ubiquitin. In addition, feasibility of the proposed methodology for measuring several residual dipolar couplings (RDCs) simultaneously is assessed.
Puttonen
Eetu
E
NMR Laboratory, Program in Structural Biology and Biophysics, Institute of Biotechnology, P.O. Box 65, FI-00014, University of Helsinki, Helsinki, Finland.
Tossavainen
Helena
H
Permi
Perttu
P
D002247:Carbon Isotopes / Q000032:analysis; D006801:Humans; D006859:Hydrogen / Q000032:analysis; D009587:Nitrogen Isotopes / Q000032:analysis; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D011487:Protein Conformation; D011506:Proteins / Q000737:chemistry*; D025801:Ubiquitin / Q000737:chemistry
D002247:Carbon Isotopes; D009587:Nitrogen Isotopes; D011506:Proteins; D025801:Ubiquitin; D006859:Hydrogen