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Adding an unnatural covalent bond to proteins through proximity-enhanced bioreactivity.

ABSTRACT: Natural proteins often rely on the disulfide bond to covalently link side chains. Here we genetically introduce a new type of covalent bond into proteins by enabling an unnatural amino acid to react with a proximal cysteine. We demonstrate the utility of this bond for enabling irreversible binding between an affibody and its protein substrate, capturing peptide-protein interactions in mammalian cells, and improving the photon output of fluorescent proteins.

SUBMITTER: Xiang Z

PROVIDER: S-EPMC3882359 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature

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Adding an unnatural covalent bond to proteins through proximity-enhanced bioreactivity.

Xiang Zheng Z Ren Haiyan H Hu Ying S YS Coin Irene I Wei Jing J Cang Hu H Wang Lei L

Nature methods 20130804 9

Natural proteins often rely on the disulfide bond to covalently link side chains. Here we genetically introduce a new type of covalent bond into proteins by enabling an unnatural amino acid to react with a proximal cysteine. We demonstrate the utility of this bond for enabling irreversible binding between an affibody and its protein substrate, capturing peptide-protein interactions in mammalian cells, and improving the photon output of fluorescent proteins. ...[more]

PMID: 23913257

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