title: New techniques for the measurement of C'N and C'H(N) J coupling constants across hydrogen bonds in proteins.
abstract: Two new two- or three-dimensional NMR methods for measuring (3h)J(C'N) and (2h)J(C'H) coupling constants across hydrogen bonds in proteins are presented. They are tailored to suit the size of the TROSY effect, i.e., the degree of interference between dipolar and chemical shift anisotropy relaxation mechanisms. The methods edit 2D or 3D spectra into two separate subspectra corresponding to the two possible spin states of the (1)H(N) spin during evolution of (13)CO coherences. This allows (2h)J(C'H) to be measured in an E.COSY-type way while (3h)J(C'N) can be measured in the so-called quantitative way provided a reference spectrum is also recorded. A demonstration of the new methods is shown for the (15)N,(13)C-labeled protein chymotrypsin inhibitor 2.
authors.affiliation: Department of Chemistry, Carlsberg Laboratory, Gamle Carlsberg Vej 10, Valby, DK-2500, Denmark.
authors.forename: A
authors.initials: A
authors.lastname: Meissner
authors.forename: O W
authors.initials: OW
authors.lastname: Sorensen
mesh_terms: D002244:Carbon / Q000737:chemistry*; D002247:Carbon Isotopes; D002918:Chymotrypsin / Q000037:antagonists & inhibitors; D004578:Electron Spin Resonance Spectroscopy; D006859:Hydrogen / Q000737:chemistry*; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D009584:Nitrogen / Q000737:chemistry*; D009587:Nitrogen Isotopes; D010455:Peptides / Q000737:chemistry; D010940:Plant Proteins; D011506:Proteins / Q000737:chemistry*; D015842:Serine Proteinase Inhibitors / Q000737:chemistry
chemical_list: D002247:Carbon Isotopes; D009587:Nitrogen Isotopes; D010455:Peptides; D010940:Plant Proteins; D011506:Proteins; D015842:Serine Proteinase Inhibitors; C093336:chymotrypsin inhibitor 2; D002244:Carbon; D006859:Hydrogen; D002918:Chymotrypsin; D009584:Nitrogen