title: [Antagonism against Beauveria bassiana by lipopeptide metabolites produced by entophyte Bacillus amyloliquefaciens strain SWB16].
abstract: OBJECTIVE
  We screened bacterial strains that have strong antagonism against Beauveria bassiana, an important pathogen of silkworm industry, and detected the antagonistic activity of lipopeptide metabolites.
  
  
  METHODS
  We identified bacterium SWB16 by morphological observation, physiological and biochemical experiments, 16SrRNA, and gyrA gene sequence analysis, tested antagonistic activity of strain SWB16 against Beauveria bassiana by measuring the inhibition zone diameter using filter paper diffusion method (Kirby-Bauer method), obtained lipopeptide metabolites of the strain using methanol extraction and observed the antagonism of strain SWB16 lipopeptide extracts against the conidia and hyphae of Beauveria bassiana, detected main ingredients and genes of lipopeptide metabolites by high-performance liquid chromatography-mass spectrometry and PCR amplification.
  
  
  RESULTS
  SWB16 isolated from tissue of plant Dioscorea zingiberensis C. H. Wright belongs to Bacillus amyloliquefaciens and showed high antagonistic activity to Beauveria bassiana, and the lipopeptide extracts of isolate SWB16 exhibited significant inhibition to conidial germination and mycelial growth of Beauveria bassiana. The result of mass spectrometric detection indicated main component of the lipopeptide metabolites were fengcin and iturin, and genes fenB, ituA involved in the synthesis of them were amplified in the genome.
  
  
  CONCLUSIONS
  Bacillus amyloliquefaciens strain SWB16 could produce lipopeptide antibiotics with strong antagonism to the entomopathogenic fungus Beauveria bassiana, and the results suggested that strain SWB16 has potential application value for controlling white muscardine of economic insects including silkworm.
authors.forename: Jingjie
authors.initials: J
authors.lastname: Wang
authors.forename: Dongyang
authors.initials: D
authors.lastname: Zhao
authors.forename: Yonggui
authors.initials: Y
authors.lastname: Liu
authors.forename: Xiang
authors.initials: X
authors.lastname: Ao
authors.forename: Rui
authors.initials: R
authors.lastname: Fan
authors.forename: Zhengqiao
authors.initials: Z
authors.lastname: Duan
authors.forename: Yanping
authors.initials: Y
authors.lastname: Liu
authors.forename: Qianqian
authors.initials: Q
authors.lastname: Chen
authors.forename: Zhixiong
authors.initials: Z
authors.lastname: Jin
authors.forename: Yongji
authors.initials: Y
authors.lastname: Wan
mesh_terms: D000935:Antifungal Agents / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology*; D001407:Bacillus / Q000737:chemistry / Q000145:classification / Q000302:isolation & purification / Q000378:metabolism*; D052982:Beauveria / Q000187:drug effects*; D027742:Dioscorea / Q000382:microbiology*; D055666:Lipopeptides / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology*; D008969:Molecular Sequence Data; D010802:Phylogeny
chemical_list: D000935:Antifungal Agents; D055666:Lipopeptides