Biosynthesis in vitro of bacillamide intermediate-heterocyclic AlaCysthiazole by heterologous expression of nonribosomal peptide synthetase (NRPS)

• Published in: Journal of biotechnology 2019-02, Vol.292, p.5-11
• Main Authors: Zhang, Fengli, Mulati, Nayila, Wang, Yukun, Li, Yingxin, Gong, Sanqiang, Karthik, Loganathan, Sun, Wei, Li, Zhiyong
• Format: Article
• Language: English
• Subjects: Bacillamides; Bacillus atrophaeus; Heterologous expression; Nonribosomal peptide synthetase (NRPS); Thiazole
• ISSN: 0168-1656; 1873-4863
• DOI: 10.1016/j.jbiotec.2018.11.024

•Two modules of nonribosomal peptide synthetase were heterologous expressed and purified.•In vitro set up a biosynthetic reaction system of nonribosomal peptide.•Bacillamide C intermediate- heterocyclic AlaCysthiazole was formed. Bacillamide C, a potential natural antialgae active compound, is produced by Bacillus atrophaeus C89 derived from marine sponge Dysidea avara. A nonribosomal peptide synthetase (NRPS) cluster is hypothesized to be involved in the biosynthesis of bacillamide C. The NRPS with a domain string of A1-PCP1-Cy-A2-PCP2-C can be divided into three functional modules. After heterologous expression and purification of module A1-PCP1 and module Cy-A2-PCP2, their catalytic activities were biochemically proven in vitro by the reaction with the apo-PCP domain transformed to the holo-PCP domain through a phosphopantetheinyl transferase, ATP, and substrate amino acids. Five– membered heterocyclic AlaCysthiazole with molecular weight of 172.0389 was detected. This proved the formation of the heterocyclic dipeptide AlaCysthiazole, which is considered to be a building block for the biosynthesis of bacillamide. This study provides a basis for further biosynthesis of bacillamides.