ISSN:
1573-5001
Keywords:
Vicinal coupling constants
;
φ Torsion angle
;
Karplus parametrization
;
Desulfovibrio vulgaris flavodoxin
;
Isotopic labelling
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
Notes:
Abstract A triple-resonance NMR technique suitable for the determination ofcarbonyl-related couplings in polypeptide systems is introduced. Theapplication of three novel pulse sequences to uniformly13C/15N-enriched proteins yields E.COSY-likemultiplet patterns exhibiting either one of the3J(C′i−1,Hi α), 3J(C′i−1,Ci β) and3J(C′i−1,C′i)coupling constants in the indirectly detected 13C′dimension, depending on the passive spin selected. The experiments aredemonstrated with oxidized flavodoxin from Desulfovibrio vulgaris. On thebasis of the J-values measured and the backbone φ-angles derived from ahigh-resolution X-ray structure of the protein, the three associated Karplusequations were reparametrized. The root-mean-square differences between theexperimental coupling constants and those predicted by the optimized Karpluscurves are 0.41, 0.33 and 0.32 Hz for3J(C′i−1,Hi α),3J(C′i−1,Ci β) and3J(C′i−1,C′i),respectively. The results are compared with the Karplus parameters previouslypublished for the same couplings.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1018355327792
