Open AccessTwo distinct structures of α‐conotoxin GI in aqueous solution
Author(s) -
Maslennikov Innokenty V.,
Sobol Alexander G.,
Gladky Konstantin V.,
Lugovskoy Alexey A.,
Ostrovsky Andrey G.,
Tsetlin Victor I.,
Ivanov Vadim T.,
Arseniev Alexander S.
Publication year - 1998
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1046/j.1432-1327.1998.2540238.x
Subject(s) - chemistry , folding (dsp implementation) , aqueous solution , crystallography , pairwise comparison , minor (academic) , protein folding , stereochemistry , mathematics , biochemistry , political science , law , electrical engineering , engineering , statistics
The detailed analysis of conformational space of α‐conotoxin GI in aqueous solution has been performed on the basis of two‐dimensional NMR spectroscopy data using multiconformational approach. As the result, two topologically distinct interconvertible sets of GI conformations (populations of 78 % and 22 %) have been found. A common feature of the two sets is the Asn4‐Cys7 β‐turn. The Gly8 to Tyr11 region has a structure of right‐handed helical turn in the major set and two sequential bends in the minor one. N‐terminus and C‐terminus also have different orientations, anti‐parallel in the major conformational set and parallel in the minor one. An average pairwise rmsd for backbone heavy atoms is 0.56 Å in the major set, 0.23 Å in the minor, and 1.85 Å between the structures of the two sets. The X‐ray structure of GI [Guddat, L. W., Martin, J. A., Shan, L., Edmundson, A. B. & Gray, W. R. (1996) Biochemistry 35 , 11 329−11 335] has the same folding pattern as the major NMR set, the average backbone rmsd between the two structures being 0.77 Å.