title: [Engineering and heterologous expression of a nikkomycin biosynthetic gene cluster].
abstract: OBJECTIVE
  We expressed a nikkomycin biosynthetic gene cluster in the well-characterized surrogate Streptomyces coelicolor M1146.
  
  
  METHODS
  By using PCR-targeting method, we replaced the promoters of sanG and sanF in pNIK, which contains nikkomycin biosynthetic gene cluster, with the hrdB promoter to generate pNIKm. We transferred pNIK and pNIKm into S. coelicolor M1146 by intergeneric conjugation and obtained M1146-NIK and M1146-NIKm, respectively. We then evaluated expression of the gene cluster in the heterologous host by RT-PCR. Furthermore, we also compared the antifugal activity and nikkomycin production of M1146-NIK and M1146-NIKm by bioassay against Alternaria longipes and HPLC analysis.
  
  
  RESULTS
  M1146-NIK and M1146-NIKm exhibited antifungal activity, and they can produce a trace amount of nikkomycin X, nikkomycin Z and pseudo-Z. There was a substantial accumulation of uridine in M1146-NIK, whereas substantial accumulations of uridine, ribofuranosyl-4-formyl-4-imidazolone and pyridylhomothreonine were observed in M1146-NIKm.
  
  
  CONCLUSIONS
  We successfully expressed the nikkomycin biosynthetic gene cluster in the heterologous host and identified nikkomycins and some of its key biosynthetic intermediates. This study will provide the basis for enzymatic reaction of the condensation between the two nikkomycin moieties and for the generation of hybrid antibiotics by combinatorial biosynthesis.
authors.forename: Lu
authors.initials: L
authors.lastname: Wang
authors.forename: Deyao
authors.initials: D
authors.lastname: Du
authors.forename: Jin'e
authors.initials: J
authors.lastname: Li
authors.forename: Yuqing
authors.initials: Y
authors.lastname: Tian
authors.forename: Hao
authors.initials: H
authors.lastname: Liu
authors.forename: Guoqing
authors.initials: G
authors.lastname: Niu
authors.forename: Huarong
authors.initials: H
authors.lastname: Tan
mesh_terms: D000617:Aminoglycosides / Q000096:biosynthesis* / Q000737:chemistry; D000935:Antifungal Agents / Q000737:chemistry / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D003001:Cloning, Molecular; D060847:Metabolic Engineering; D005810:Multigene Family; D011401:Promoter Regions, Genetic; D013302:Streptomyces / Q000235:genetics* / Q000378:metabolism*
chemical_list: D000617:Aminoglycosides; D000935:Antifungal Agents; D001426:Bacterial Proteins; C011952:nikkomycin