ISSN:
1573-5001
Keywords:
carbon-carbon J coupling
;
E. COSY
;
Karplus equation
;
φ angle
;
3D NMR
;
ubiquitin
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
Notes:
Abstract A [CO]HN(CA)CB-E.COSY pulse scheme is described for measurement of three-bond couplings, 3JC′Cβ, between carbonyl and aliphatic Cβ carbons in ubiquitin, uniformly enriched with 13C and 15N. A Karplus relation, 3JC′Cβ = 1.28 cos2(φ - 120°) -1.02 cos(φ - 120°) +0.30 Hz, is obtained by correlating the 3JC′Cβ values measured for human ubiquitin with backbone φ angles from its crystal structure. As predicted, the new Karplus parametrization yields 3JC′Cβ values slightly larger than previously obtained by quantitative J correlation [Hu, J.-S. and Bax, A. (1997) J. Am. Chem. Soc., 119, 6360-6368], but considerably smaller than what has been reported on the basis of other E.COSY-type measurements carried out on flavodoxin.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1008241904271
Permalink
