Iannuzzelli Jacob A, Fasan Rudi
Department of Chemistry , University of Rochester , Rochester , New York 14627 , USA . Email:
Chem Sci. 2020 May 27;11(24):6202-6208. doi: 10.1039/d0sc01699c. eCollection 2020 Jun 28.
The macrocyclization of recombinant polypeptides by means of genetically encodable non-canonical amino acids has recently provided an attractive strategy for the screening and discovery of macrocyclic peptide inhibitors of protein-protein interactions. Here, we report the development of an expanded suite of electrophilic unnatural amino acids (eUAAs) useful for directing the biosynthesis of genetically encoded thioether-bridged macrocyclic peptides in bacterial cells (). These reagents are shown to provide efficient access to a broad range of macrocyclic peptide scaffolds spanning from 2 to 20 amino acid residues, with the different eUAAs offering complementary reactivity profiles toward mediating short- long-range macrocyclizations. Swapping of the eUAA cyclization module in a cyclopeptide inhibitor of streptavidin and Keap1 led to compounds with markedly distinct binding affinity toward the respective target proteins, highlighting the effectiveness of this strategy toward tuning the structural and functional properties of bioactive macrocyclic peptides. The peptide cyclization strategies reported here expand opportunities for the combinatorial biosynthesis of natural product-like peptide macrocycles in bacterial cells or in combination with display platforms toward the discovery of selective agents capable of targeting proteins and protein-mediated interactions.
利用可遗传编码的非天然氨基酸对重组多肽进行大环化，最近为筛选和发现蛋白质-蛋白质相互作用的大环肽抑制剂提供了一种有吸引力的策略。在此，我们报告了一套扩展的亲电非天然氨基酸（eUAA）的开发，这些氨基酸可用于指导细菌细胞中可遗传编码的硫醚桥连大环肽的生物合成。这些试剂被证明能有效地获得广泛的大环肽支架，其氨基酸残基数从2到20不等，不同的eUAA在介导短程和长程大环化方面具有互补的反应活性。在链霉亲和素和Keap1的环肽抑制剂中交换eUAA环化模块，得到了对各自靶蛋白具有明显不同结合亲和力的化合物，突出了该策略在调节生物活性大环肽的结构和功能特性方面的有效性。本文报道的肽环化策略为在细菌细胞中或与展示平台结合进行天然产物样肽大环的组合生物合成提供了更多机会，以发现能够靶向蛋白质和蛋白质介导相互作用的选择性试剂。
