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Enzyme-catalyzed expressed protein ligation.

ABSTRACT: Expressed protein ligation is a valuable method for protein semisynthesis that involves the reaction of recombinant protein C-terminal thioesters with N-terminal cysteine (N-Cys)-containing peptides, but the requirement of a Cys residue at the ligation junction can limit the utility of this method. Here we employ subtiligase variants to efficiently ligate Cys-free peptides to protein thioesters. Using this method, we have more accurately determined the effect of C-terminal phosphorylation on the tumor suppressor protein PTEN.

SUBMITTER: Henager SH

PROVIDER: S-EPMC5088058 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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Enzyme-catalyzed expressed protein ligation.

Henager Samuel H SH Chu Nam N Chen Zan Z Bolduc David D Dempsey Daniel R DR Hwang Yousang Y Wells James J Cole Philip A PA

Nature methods 20160926 11

Expressed protein ligation is a valuable method for protein semisynthesis that involves the reaction of recombinant protein C-terminal thioesters with N-terminal cysteine (N-Cys)-containing peptides, but the requirement of a Cys residue at the ligation junction can limit the utility of this method. Here we employ subtiligase variants to efficiently ligate Cys-free peptides to protein thioesters. Using this method, we have more accurately determined the effect of C-terminal phosphorylation on the ...[more]

PMID: 27669326

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