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Structural characterization of a beta-turn mimic within a protein-protein interface.

ABSTRACT: ?-Turns are secondary structure elements not only exposed on protein surfaces, but also frequently found to be buried in protein-protein interfaces. Protein engineering so far considered mainly the backbone-constraining properties of synthetic ?-turn mimics as parts of surface-exposed loops. A ?-turn mimic, Hot?Tap, that is available in gram amounts, provides two hydroxyl groups that enhance its turn-inducing properties besides being able to form side-chain-like interactions. NMR studies on cyclic hexapeptides harboring the Hot?Tap dipeptide proved its strong ?-turn-inducing capability. Crystallographic analyses of the trimeric fibritin-foldon/Hot?Tap hybrid reveal at atomic resolution how Hot?Tap replaces a ?I'-turn by a ?II'-type structure. Furthermore, Hot?Tap adapts to the complex protein environment by participating in several direct and water-bridged interactions across the foldon trimer interface. As building blocks, ?-turn mimics capable of both backbone and side-chain mimicry may simplify the design of synthetic proteins.

SUBMITTER: Eckhardt B

PROVIDER: S-EPMC2972999 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature

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Structural characterization of a beta-turn mimic within a protein-protein interface.

Eckhardt Björn B Grosse Wolfgang W Essen Lars-Oliver LO Geyer Armin A

Proceedings of the National Academy of Sciences of the United States of America 20101011 43

β-Turns are secondary structure elements not only exposed on protein surfaces, but also frequently found to be buried in protein-protein interfaces. Protein engineering so far considered mainly the backbone-constraining properties of synthetic β-turn mimics as parts of surface-exposed loops. A β-turn mimic, Hot═Tap, that is available in gram amounts, provides two hydroxyl groups that enhance its turn-inducing properties besides being able to form side-chain-like interactions. NMR studies on cycl ...[more]

PMID: 20937907

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Structural characterization of a beta-turn mimic within a protein-protein interface.

Publications

Structural characterization of a beta-turn mimic within a protein-protein interface.

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