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Traceless and site-specific ubiquitination of recombinant proteins.

ABSTRACT: Protein ubiquitination is a post-translational modification that regulates almost all aspects of eukaryotic biology. Here we discover the first routes for the efficient site-specific incorporation of ?-thiol-L-lysine (7) and ?-hydroxy-L-lysine (8) into recombinant proteins, via evolution of a pyrrolysyl-tRNA synthetase/tRNA(CUA) pair. We combine the genetically directed incorporation of 7 with native chemical ligation and desulfurization to yield an entirely native isopeptide bond between substrate proteins and ubiquitin. We exemplify this approach by demonstrating the synthesis of a ubiquitin dimer and the first synthesis of ubiquitinated SUMO.

SUBMITTER: Virdee S

PROVIDER: S-EPMC3135006 | biostudies-literature | 2011 Jul

REPOSITORIES: biostudies-literature

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Traceless and site-specific ubiquitination of recombinant proteins.

Virdee Satpal S Kapadnis Prashant B PB Elliott Thomas T Lang Kathrin K Madrzak Julia J Nguyen Duy P DP Riechmann Lutz L Chin Jason W JW

Journal of the American Chemical Society 20110628 28

Protein ubiquitination is a post-translational modification that regulates almost all aspects of eukaryotic biology. Here we discover the first routes for the efficient site-specific incorporation of δ-thiol-L-lysine (7) and δ-hydroxy-L-lysine (8) into recombinant proteins, via evolution of a pyrrolysyl-tRNA synthetase/tRNA(CUA) pair. We combine the genetically directed incorporation of 7 with native chemical ligation and desulfurization to yield an entirely native isopeptide bond between substr ...[more]

PMID: 21710965

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