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Enzyme-catalyzed macrocyclization of long unprotected peptides.

ABSTRACT: A glutathione S-transferase (GST) catalyzed macrocyclization reaction for peptides up to 40 amino acids in length is reported. GST catalyzes the selective S(N)Ar reaction between an N-terminal glutathione (GSH, ?-Glu-Cys-Gly) tag and a C-terminal perfluoroaryl-modified cysteine on the same polypeptide chain. Cyclic peptides ranging from 9 to 24 residues were quantitatively produced within 2 h in aqueous pH = 8 buffer at room temperature. The reaction was highly selective for cyclization at the GSH tag, enabling the combination of GST-catalyzed ligation with native chemical ligation to generate a large 40-residue peptide macrocycle.

SUBMITTER: Zhang C

PROVIDER: S-EPMC4372082 | biostudies-other | 2014 Jul

REPOSITORIES: biostudies-other

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Enzyme-catalyzed macrocyclization of long unprotected peptides.

Zhang Chi C Dai Peng P Spokoyny Alexander M AM Pentelute Bradley L BL

Organic letters 20140708 14

A glutathione S-transferase (GST) catalyzed macrocyclization reaction for peptides up to 40 amino acids in length is reported. GST catalyzes the selective S(N)Ar reaction between an N-terminal glutathione (GSH, γ-Glu-Cys-Gly) tag and a C-terminal perfluoroaryl-modified cysteine on the same polypeptide chain. Cyclic peptides ranging from 9 to 24 residues were quantitatively produced within 2 h in aqueous pH = 8 buffer at room temperature. The reaction was highly selective for cyclization at the G ...[more]

PMID: 25002256

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