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PubMed · 16155946

Engineering an affinity tag for genetically encoded cyclic peptides.

Todd A Naumann·Sergey N Savinov·Stephen J Benkovic
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Abstract

Peptide expression libraries are valuable probes of cellular function. SICLOPPS technology merges the principal advantages of both genetic methods and small-molecule approaches in yielding superior library sizes of operationally stable, structurally well-defined entities with an established biological and medicinal record. Here, we describe development, application, and the first-generation library implementation of an expressed affinity tag for a library of cyclic peptides. A tripeptide streptavidin-binding motif (HPQ) proved to be compatible with presentation from a backbone cyclized template. A resulting peptide was employed as a sensitive indicator of peptide splicing, expression, and recovery as well as an affinity tag for one-step purification. Specific recognition of the tag by streptavidin was also critical for an analysis of intein mutants. Finally, the initially identified probe was used as a template for design of a streptavidin-responsive cyclic peptide library.

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Amino Acid MotifsInteinsPeptide LibraryPeptides, CyclicProtein BindingProtein EngineeringStreptavidinJournal ArticleResearch Support, N.I.H., Extramural

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Todd A Naumann, Sergey N Savinov, Stephen J Benkovic. 2005-12-30. Engineering an affinity tag for genetically encoded cyclic peptides.. https://doi.org/10.1002/bit.20644

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