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A straight path to circular proteins.

ABSTRACT: Folding and stability are parameters that control protein behavior. The possibility of conferring additional stability on proteins has implications for their use in vivo and for their structural analysis in the laboratory. Cyclic polypeptides ranging in size from 14 to 78 amino acids occur naturally and often show enhanced resistance toward denaturation and proteolysis when compared with their linear counterparts. Native chemical ligation and intein-based methods allow production of circular derivatives of larger proteins, resulting in improved stability and refolding properties. Here we show that circular proteins can be made reversibly with excellent efficiency by means of a sortase-catalyzed cyclization reaction, requiring only minimal modification of the protein to be circularized.

SUBMITTER: Antos JM

PROVIDER: S-EPMC2708896 | biostudies-literature | 2009 Jun

REPOSITORIES: biostudies-literature

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A straight path to circular proteins.

Antos John M JM Popp Maximilian Wei-Lin MW Ernst Robert R Chew Guo-Liang GL Spooner Eric E Ploegh Hidde L HL

The Journal of biological chemistry 20090409 23

Folding and stability are parameters that control protein behavior. The possibility of conferring additional stability on proteins has implications for their use in vivo and for their structural analysis in the laboratory. Cyclic polypeptides ranging in size from 14 to 78 amino acids occur naturally and often show enhanced resistance toward denaturation and proteolysis when compared with their linear counterparts. Native chemical ligation and intein-based methods allow production of circular der ...[more]

PMID: 19359246

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