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In vivo biosynthesis of an Ala-scan library based on the cyclic peptide SFTI-1.

ABSTRACT: We present the in vivo biosynthesis of wild-type sunflower trypsin inhibitor 1 (SFTI-1) inside E. coli cells using an intramolecular native chemical ligation in combination with a modified protein splicing unit. SFTI-1 is a small backbone cyclized polypeptide with a single disulfide bridge. A small library containing multiple Ala mutants was also biosynthesized and its activity was assayed using a trypsin-binding assay. This study clearly demonstrates the exciting possibility of generating large cyclic peptide libraries in live E. coli cells, and is a critical first step for developing in vivo screening and directed evolution technologies using the cyclic peptide SFTI-1 as a molecular scaffold.

SUBMITTER: Austin J

PROVIDER: S-EPMC2936557 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature

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In vivo biosynthesis of an Ala-scan library based on the cyclic peptide SFTI-1.

Austin Jeffrey J Kimura Richard H RH Woo Youn-Hi YH Camarero Julio A JA

Amino acids 20090814 5

We present the in vivo biosynthesis of wild-type sunflower trypsin inhibitor 1 (SFTI-1) inside E. coli cells using an intramolecular native chemical ligation in combination with a modified protein splicing unit. SFTI-1 is a small backbone cyclized polypeptide with a single disulfide bridge. A small library containing multiple Ala mutants was also biosynthesized and its activity was assayed using a trypsin-binding assay. This study clearly demonstrates the exciting possibility of generating large ...[more]

PMID: 19685144

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