Cation-pi interactions in structural biology.

J P Gallivan; D A Dougherty

doi:10.1073/pnas.96.17.9459

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Cation-pi interactions in structural biology.

J P Gallivan·D A Dougherty

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Abstract

Cation-pi interactions in protein structures are identified and evaluated by using an energy-based criterion for selecting significant sidechain pairs. Cation-pi interactions are found to be common among structures in the Protein Data Bank, and it is clearly demonstrated that, when a cationic sidechain (Lys or Arg) is near an aromatic sidechain (Phe, Tyr, or Trp), the geometry is biased toward one that would experience a favorable cation-pi interaction. The sidechain of Arg is more likely than that of Lys to be in a cation-pi interaction. Among the aromatics, a strong bias toward Trp is clear, such that over one-fourth of all tryptophans in the data bank experience an energetically significant cation-pi interaction.

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Arginine Cations Histidine Lysine Models, Chemical Models, Molecular Phenylalanine Protein Conformation Proteins Tryptophan Tyrosine Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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J P Gallivan, D A Dougherty. 1999-08-17. Cation-pi interactions in structural biology.. https://doi.org/10.1073/pnas.96.17.9459

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