title: A J-multiplied HMQC (MJ-HMQC) experiment for measuring (3)J(HNHalpha) coupling constants.
abstract: The J-multiplied HSQC experiment (MJ-HSQC: S. Heikkinen et al., J. Magn. Reson 137, 243 (1999)) amplifies J coupling constants m times and allows direct observation of the (3)J(HNHalpha) coupling constants of peptides and proteins (<10 kDa). The drawbacks to this method are line broadening in the f(1)-dimension and lower sensitivity. In the J-multiplied HMQC (MJ-HMQC) experiment described here, the PEP-HSQC pulse sequence is replaced by a sensitivity-enhanced HMQC section, and the total decay time for the J-coupling and the chemical shift evolution is shortened by a period of t(1). This experiment affords narrower linewidth and enhances the sensitivity by 34%, on an average of 105 well-isolated peaks, when compared with the MJ-HSQC experiment.
authors.affiliation: Department of Biochemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
authors.forename: Y
authors.initials: Y
authors.lastname: Xia
authors.forename: X
authors.initials: X
authors.lastname: Kong
authors.forename: N
authors.initials: N
authors.lastname: Ip
authors.forename: G
authors.initials: G
authors.lastname: Zhu
mesh_terms: D000465:Algorithms; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D009587:Nitrogen Isotopes; D010455:Peptides / Q000737:chemistry*; D011506:Proteins / Q000737:chemistry*; D020801:Receptor, Ciliary Neurotrophic Factor / Q000737:chemistry
chemical_list: D009587:Nitrogen Isotopes; D010455:Peptides; D011506:Proteins; D020801:Receptor, Ciliary Neurotrophic Factor