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A Highly Efficient Synthesis of Polyubiquitin Chains.

ABSTRACT: A robust, microwave-assisted, highly efficient, solid-phase peptide synthesis method for preparing isopeptide-linked 62-mer and 76-mer isoubiquitins and polyubiquitin is developed. The strategy avoids the use of costly resins and pseudoprolines, and the isopeptide-linked building blocks can be assembled with high initial purity within 1 day. All seven diubiquitins are successfully synthesized on a multi-milligram scale; a four-segment, three-ligation method is used to obtain a K33-/K11-linked mixed triubiquitin in excellent yield. Circular dichroism and crystallographic analyses are used to verify the structures of the well-folded, synthetic polyubiquitin chains. The facile synthetic strategy is expected to be generally applicable for the rapid synthesis of isopeptide-linked isoUbs and to pave the way for the study of longer polyubiquitin chains.

SUBMITTER: Qu Q

PROVIDER: S-EPMC6051384 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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A Highly Efficient Synthesis of Polyubiquitin Chains.

Qu Qian Q Pan Man M Gao Shuai S Zheng Qing-Yun QY Yu Yuan-Yuan YY Su Jia-Can JC Li Xiang X Hu Hong-Gang HG

Advanced science (Weinheim, Baden-Wurttemberg, Germany) 20180514 7

A robust, microwave-assisted, highly efficient, solid-phase peptide synthesis method for preparing isopeptide-linked 62-mer and 76-mer isoubiquitins and polyubiquitin is developed. The strategy avoids the use of costly resins and pseudoprolines, and the isopeptide-linked building blocks can be assembled with high initial purity within 1 day. All seven diubiquitins are successfully synthesized on a multi-milligram scale; a four-segment, three-ligation method is used to obtain a K33-/K11-linked mi ...[more]

PMID: 30027052

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