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Updated: Sep 20, 2026

Unraveling Entropic Rate Acceleration Induced by Solvent Dynamics in Membrane Enzymes
Published on: January 16, 2016
On the impossibility of determination of stepwise binding constants for the 1 : 2 complex of (+)-camphor with
Helena Dodziuk1, Krzysztof S Nowinski, Wiktor Kozminski
1Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland. dodziuk@ichf.edu.pl
Abstract:
Knowledge of stepwise binding constants for complexes with higher than 1:1 stoichiometry would allow one to study the cooperativity of their formation. However, a detailed analysis of partitioning of the overall binding constant beta 12 determined by NMR titrations for the 1:2 complex of (+)-camphor with alpha-cyclodextrin into the stepwise ones K1 and K2 carried out analogously to published procedures revealed that the partitioning cannot be carried out unequivocally for K1 << K2. The programs for partitioning cannot be used as a black box and a satisfactory reproduction of the experimental dependence of relative shifts as a function of relative CD concentration should not be the only criterion of the reliability of the stepwise binding constants obtained using such programs.
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