PT - JOURNAL ARTICLE AU - Alexander A. Vinogradov AU - Morito Shimomura AU - Yuki Goto AU - Taro Ozaki AU - Shumpei Asamizu AU - Yoshinori Sugai AU - Hiroaki Suga AU - Hiroyasu Onaka TI - Minimal lactazole scaffold for <em>in vitro</em> production of pseudo-natural thiopeptides AID - 10.1101/807206 DP - 2019 Jan 01 TA - bioRxiv PG - 807206 4099 - http://biorxiv.org/content/early/2019/10/16/807206.short 4100 - http://biorxiv.org/content/early/2019/10/16/807206.full AB - Lactazole A is a cryptic thiopeptide from Streptomyces lactacystinaeus, encoded by a compact 9.8 kb biosynthetic gene cluster. Here, we established a platform for in vitro biosynthesis of lactazole A, referred to as the FIT-Laz system, via a combination of the flexible in vitro translation (FIT) system with recombinantly produced lactazole biosynthetic enzymes. Systematic dissection of lactazole biosynthesis revealed remarkable substrate tolerance of the biosynthetic enzymes, and led to the development of the “minimal lactazole scaffold”, a construct requiring only 6 post-translational modifications for macrocyclization. Efficient assembly of such minimal thiopeptides with FIT-Laz enabled access to diverse lactazole analogs with 10 consecutive mutations, 14- to 62-membered macrocycles, and up to 18 amino acid-long tail regions. Moreover, utilizing genetic code reprogramming, we demonstrated synthesis of pseudo-natural lactazoles containing 4 non-proteinogenic amino acids. This work opens possibilities in exploring novel sequence space of pseudo-natural thiopeptides.