Hydrophobicity regained.

P A Karplus

doi:10.1002/pro.5560060618

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PubMed · 9194190

Hydrophobicity regained.

P A Karplus

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Abstract

A widespread practice is to use free energies of transfer between organic solvents and water (delta G0transfer to define hydrophobicity scales for the amino acid side chains. A comparison of four delta G0transfer scales reveals that the values for hydrogen-bonding side chains are highly dependent on the non-aqueous environment. This property of polar side chains violates the assumptions underlying the paradigm of equating delta G0transfer with hydrophobicity or even with a generic solvation energy that is directly relevant to protein stability and ligand binding energetics. This simple regaining of the original concept of hydrophobicity reveals a flaw in approaches that use delta G0transfer values to derive generic estimates of the energetics of the burial of polar groups, and allows the introduction of a "pure" hydrophobicity scale for the amino acid residues.

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Amino Acids Hydrogen Bonding Models, Chemical Protein Folding Solvents Thermodynamics Water Comparative Study Journal Article Research Support, Non-U.S. Gov't

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P A Karplus. 1997. Hydrophobicity regained.. https://doi.org/10.1002/pro.5560060618

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