TY - JOUR A1 - Reyna-González, Emmanuel A1 - Schmid, Bianca A1 - Petras, Daniel A1 - Süssmuth, Roderich D. A1 - Dittmann, Elke T1 - Leader Peptide-Free In Vitro Reconstitution of Microviridin Biosynthesis Enables Design of Synthetic Protease-Targeted Libraries JF - Angewandte Chemie : a journal of the Gesellschaft Deutscher Chemiker ; International edition N2 - Microviridins are a family of ribosomally synthesized and post-translationally modified peptides with a highly unusual architecture featuring non-canonical lactone as well as lactam rings. Individual variants specifically inhibit different types of serine proteases. Here we have established an efficient in vitro reconstitution approach based on two ATP-grasp ligases that were constitutively activated using covalently attached leader peptides and a GNAT-type N-acetyltransferase. The method facilitates the efficient in vitro one-pot transformation of microviridin core peptides to mature microviridins. The engineering potential of the chemo-enzymatic technology was demonstrated for two synthetic peptide libraries that were used to screen and optimize microviridin variants targeting the serine proteases trypsin and subtilisin. Successive analysis of intermediates revealed distinct structure-activity relationships for respective target proteases. KW - biosynthesis KW - cyanobacteria KW - microviridins KW - natural products KW - peptides Y1 - 2016 U6 - https://doi.org/10.1002/anie.201604345 SN - 1433-7851 SN - 1521-3773 VL - 55 SP - 9398 EP - 9401 PB - Wiley-VCH CY - Weinheim ER -