ISSN:
1573-5001
Keywords:
3D triple-resonance NMR
;
1H,1H and 1H,13C J-coupling constants
;
E.COSY
;
ϕ-angle constraints
;
Desulfovibrio vulgaris flavodoxin
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
Notes:
Summary A set of three-dimensional triple-resonance experiments is described which provide $${}^{\text{3}}{\text{J}}_{{\text{H}}^{\text{N}} {\text{H}}^\alpha } $$ , $${}^{\text{3}}{\text{J}}_{{\text{H}}^{\text{N}} {\text{CO}}} $$ , $${}^3J_{H^N C^\beta } $$ and $${}^{\text{3}}{\text{J}}_{{\text{H}}^\alpha {\text{CO}}} $$ coupling constants. The pulse sequences generate E.COSY-like multiplet patterns and comprise a magnetization transfer from the amide proton to the α-proton or vice versa via the directly bound heteronuclei. For residues with the 1Hα spin resonating close to the H2O signal, a modified HNCA experiment can be employed to measure the vicinal 1HN,1Hα couplings. Ambiguities associated with the conversion of $${}^{\text{3}}{\text{J}}_{{\text{H}}^{\text{N}} {\text{H}}^\alpha } $$ values into ϕ-angle constraints for protein structure determination can be resolved with the knowledge of the heteronuclear 3J-couplings. In favourable cases, stereospecific assignments of glycine α-protons can be obtained by employing the experiments described here in combination with NOE data. The methods are applied to flavodoxin from Desulfovibrio vulgaris.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00227467
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