Cosine modulated HSQC: a rapid determination of (3)J(HNHalpha) scalar couplings in (15)N-labeled proteins.
A two-dimensional HSQC-based NMR method, (15)N-COSMO-HSQC, is presented for the rapid determination of homonuclear (3)J(HNHalpha) couplings in (15)N-labeled proteins in solution. Scalar couplings are extracted by comparing the intensity of two separate datasets recorded with and without decoupling of the (3)J(HNHalpha) during a preparation period. The scalar couplings are introduced through a cosine modulation of the peak intensities. The experiment relies on a BIRD sandwich to selectively invert all amide protons H(N) and is very simple to implement. (3)J(HNHalpha) couplings were determined using both the (15)N-COSMO-HSQC and quantitative-J on (15)N-labeled chemokine RANTES. The two experiments show well-correlated values.
Petit
Audrey
A
Université de Lausanne, Institut de Chimie Organique/BCH, CH-1015 Lausanne, Switzerland.
Vincent
Sébastien J F
SJ
Zwahlen
Catherine
C
D008433:Mathematics; D019906:Nuclear Magnetic Resonance, Biomolecular; D011506:Proteins / Q000737:chemistry*
D011506:Proteins