Microorganisms (Jul 2022)

Identification of Nematicidal Metabolites from <i>Purpureocillium lavendulum</i>

  • Rui Liu,
  • Zheng-Xue Bao,
  • Guo-Hong Li,
  • Chun-Qiang Li,
  • Shao-Lin Wang,
  • Xue-Rong Pan,
  • Ke-Qin Zhang,
  • Pei-Ji Zhao

DOI
https://doi.org/10.3390/microorganisms10071343
Journal volume & issue
Vol. 10, no. 7
p. 1343

Abstract

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Purpureocillium lavendulum is a fungus with promising biocontrol applications. Here, transcriptome data acquired during the infection of Caenorhabditis elegans by Purpureocillium lavendulum showed that the transcription of metabolite synthesis genes was significantly up-regulated after 24 and 48 h of the fungus-nematode interaction. Then, the up-regulated transcription level of lipoxygenase was confirmed by RT-qPCR. The ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) analysis of differential metabolites revealed that this interaction resulted in the emergence of new metabolites or enhanced the production of metabolites. The results of the UPLC-MS analysis and the nematicidal assay were used to establish optimal culturing conditions under which 12 metabolites, including 3 hydroxylated C18 fatty acids and 9 steroids, were isolated and identified. Among them, hydroxylated fatty acids showed pronounced nematicidal activity against Meloidogyne incognita, and two degradative sterols showed chemotaxis activity to M. incognita. This study lays a foundation for the function of lipoxygenase and its products during the infection of Purpureocillium lavendulum.

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