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Simple electrostatic model improves designed protein sequences.

ABSTRACT: Electrostatic interactions are important for both protein stability and function, including binding and catalysis. As protein design moves into these areas, an accurate description of electrostatic energy becomes necessary. Here, we show that a simple distance-dependent Coulombic function parameterized by a comparison to Poisson-Boltzmann calculations is able to capture some of these electrostatic interactions. Specifically, all three helix N-capping interactions in the engrailed homeodomain fold are recovered using the newly parameterized model. The stability of this designed protein is similar to a protein forced by sequence restriction to have beneficial electrostatic interactions.

SUBMITTER: Zollars ES

PROVIDER: S-EPMC2242593 | biostudies-literature | 2006 Aug

REPOSITORIES: biostudies-literature

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Simple electrostatic model improves designed protein sequences.

Zollars Eric S ES Marshall Shannon A SA Mayo Stephen L SL

Protein science : a publication of the Protein Society 20060705 8

Electrostatic interactions are important for both protein stability and function, including binding and catalysis. As protein design moves into these areas, an accurate description of electrostatic energy becomes necessary. Here, we show that a simple distance-dependent Coulombic function parameterized by a comparison to Poisson-Boltzmann calculations is able to capture some of these electrostatic interactions. Specifically, all three helix N-capping interactions in the engrailed homeodomain fol ...[more]

PMID: 16823032

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