Quantification of the hydrophobic interaction by simulations of the aggregation of small hydrophobic solutes in water
Data(s) |
22/05/2001
15/05/2001
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Resumo |
The hydrophobic interaction, the tendency for nonpolar molecules to aggregate in solution, is a major driving force in biology. In a direct approach to the physical basis of the hydrophobic effect, nanosecond molecular dynamics simulations were performed on increasing numbers of hydrocarbon solute molecules in water-filled boxes of different sizes. The intermittent formation of solute clusters gives a free energy that is proportional to the loss in exposed molecular surface area with a constant of proportionality of 45 ± 6 cal/mol⋅Å2. The molecular surface area is the envelope of the solute cluster that is impenetrable by solvent and is somewhat smaller than the more traditional solvent-accessible surface area, which is the area transcribed by the radius of a solvent molecule rolled over the surface of the cluster. When we apply a factor relating molecular surface area to solvent-accessible surface area, we obtain 24 cal/mol⋅Å2. Ours is the first direct calculation, to our knowledge, of the hydrophobic interaction from molecular dynamics simulations; the excellent qualitative and quantitative agreement with experiment proves that simple van der Waals interactions and atomic point-charge electrostatics account for the most important driving force in biology. |
Identificador |
/pmc/articles/PMC33406/ /pubmed/11353861 |
Idioma(s) |
en |
Publicador |
The National Academy of Sciences |
Direitos |
Copyright © 2001, The National Academy of Sciences |
Palavras-Chave | #Physical Sciences |
Tipo |
Text |