title: Characterization of the aurantimycin biosynthetic gene cluster and enhancing its production by manipulating two pathway-specific activators in Streptomyces aurantiacus JA 4570.
abstract: BACKGROUND
  Aurantimycin (ATM), produced by Streptomyces aurantiacus JA 4570, is a potent antimicrobial and antitumor antibiotic. Although the chemical structure of ATM is highly distinctive and features a cyclohexadepsipeptide scaffold attached with a C14acyl side chain, little is known about its biosynthetic pathway and regulatory mechanism.
  
  
  RESULTS
  In this work, we report the identification and characterization of the ATM biosynthetic gene cluster from S. aurantiacus JA 4570. Targeted inactivation of artG, coding for a NRPS enzyme, completely abolished ATM production, thereof demonstrating the target gene cluster (art) is responsible for ATM biosynthesis. Moreover, four NRPS adenylation (A) domains including a freestanding enzyme ArtC have been characterized in vitro, whose substrate specificities are consistent with in silico analysis. Further genetic analysis of the two regulatory genes artB and artX unambiguously suggested both of them play positive roles in ATM biosynthesis, and ATM-A production was thus rationally enhanced to about 2.5 fold via tandem overexpression of artB and artX in S. aurantiacus JA 4570.
  
  
  CONCLUSIONS
  These results will provide the basis for the understanding of precise mechanisms for ATM biosynthesis, and open the way for both rational construction of high-production ATM producer and orient-directed generation of designer ATM derivatives via synthetic biology strategies.
authors.affiliation: Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430071, China.
authors.forename: Houyuan
authors.initials: H
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430071, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Wang
authors.affiliation: Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430071, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Wan
authors.affiliation: Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430071, China.
authors.forename: Jianzhao
authors.initials: J
authors.lastname: Qi
authors.affiliation: Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430071, China.
authors.forename: Rong
authors.initials: R
authors.lastname: Gong
authors.affiliation: Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430071, China.|State Key Laboratory of Microbial Metabolism, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai, 200030, China.
authors.forename: Zixin
authors.initials: Z
authors.lastname: Deng
authors.affiliation: Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430071, China. wqchen@whu.edu.cn.
authors.forename: Wenqing
authors.initials: W
authors.lastname: Chen
keywords: Aurantimycin; Biosynthesis; Gene cluster; Pathway-specific activators; Streptomyces