Entropy in biological binding processes: Estimation of translational entropy loss

Authors

  • Kenneth P. Murphy,

    1. Department of Biology and Biocalorimetry Center, The Johns Hopkins University, Baltimore, Maryland 21218
    Current affiliation:
    1. Department of Biochemistry, University of Iowa, Iowa City, IA 52242
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  • Dong Xie,

    1. Department of Biology and Biocalorimetry Center, The Johns Hopkins University, Baltimore, Maryland 21218
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  • Kelly S. Thompson,

    1. Department of Biology and Biocalorimetry Center, The Johns Hopkins University, Baltimore, Maryland 21218
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  • L. Mario Amzel,

    1. Department of Biophysics and Biophysical Chemistry, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
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  • Dr. Ernesto Freire

    Corresponding author
    1. Department of Biology and Biocalorimetry Center, The Johns Hopkins University, Baltimore, Maryland 21218
    • Department of Biology and Biocalorimetry Center, The Johns Hopkins University School of Medicine, Charles and 34th Streets, Baltimore, MD 21218
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Abstract

The loss of translational degrees of freedom makes an important, unfavorable contribution to the free energy of binding. Examination of experimental values suggest that calculation of this entropy using the Sackur–Tetrode equation produces largely overestimated values. Better agreement is obtained using the cratic entropy. Theoretical considerations suggest that the volumes available for the movement of a ligand in solution and in a complex are rather similar, suggesting also that the cratic entropy provides the best estimate of the loss of translational entropy. © 1994 John Wiley & Sons, Inc.

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