The Nonexistence of Specially Stabilized Hydrogen Bonds in Enzymes

Authors

Steve Scheiner, Utah State UniversityFollow
Tapas Kar, Southern Illinois University Carbondale

Document Type

Article

Journal/Book Title

Journal of the American Chemical Society

Publication Date

7-1995

Publisher

American Chemical Society

Volume

117

Abstract

Ab initio calculations are used to test a recent suggestion that enzymic catalysis can be aided by strengthening of a hydrogen bond in a key intermediate, occurring when this bond is shortened and the pK_a’s of the two groups are equalized. The requisite amount of energy is not available in electrically neutral H-bonds; no additional strengthening can be accomplished by shortening such a bond. Interaction energies where one subunit is charged, on the other hand, can be very high. These bonds are intrinsically very short, and the proton transfer profile contains a very low energy barrier. There is no special stabilization associated with the disappearance of the transfer barrier or equalization of the pK_a’s.

Comments

Originally published in the Journal of the American Chemical Society by the American Chemical Society . Publisher’s PDF available through remote link. DOI: 10.1021/ja00131a020

Recommended Citation

The Nonexistence of Specially Stabilized Hydrogen Bonds in Enzymes S. Scheiner, T. Kar J. Am. Chem. Soc. 1995 117 (26), 6970-6975.