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An improved capping unit for stabilizing the ends of associated ?-strands.

ABSTRACT: Understanding protein beta structures has been hindered by the challenge of designing small, well-folded ?-sheet systems. A ?-capping motif was previously designed to help solve this problem, but not without limitations, as the termini of this ?-cap were not fully available for chain extension. Combining Coulombic side chain attractions with a Trp/Trp edge-to-face interaction we produced a new capping motif that provided greater ?-sheet stability. This stability was maintained even in systems lacking a turn locus with a high propensity for chain direction reversal. The Coulombic cap was shown to improve ?-sheet stability in a number of difficult systems, hence providing an additional tool for protein structure and folding studies.

SUBMITTER: Anderson JM

PROVIDER: S-EPMC7450584 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature

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An improved capping unit for stabilizing the ends of associated β-strands.

Anderson Jordan M JM Kier Brandon L BL Shcherbakov Alexander A AA Andersen Niels H NH

FEBS letters 20141115 24

Understanding protein beta structures has been hindered by the challenge of designing small, well-folded β-sheet systems. A β-capping motif was previously designed to help solve this problem, but not without limitations, as the termini of this β-cap were not fully available for chain extension. Combining Coulombic side chain attractions with a Trp/Trp edge-to-face interaction we produced a new capping motif that provided greater β-sheet stability. This stability was maintained even in systems la ...[more]

PMID: 25451230

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