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Phospholipase A2 inhibitors in bacterial culture broth enhance pathogenicity of a fungus Nomuraea rileyi

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Abstract

An entomopathogenic fungus, Nomuraea rileyi, was isolated and its identity was confirmed by its internal transcribed spacer DNA sequence. The isolated N. rileyi exhibited a specific pathogenicity to lepidopteran species. This study was focused on enhancing the fungal pathogenicity by using immunosuppressive agents. In response to infection of N. rileyi, Spodoptera exigua larvae significantly induced catalytic activity of phospholipase A2 (PLA2) in three immune-associated tissues, namely hemocytes, fat body, and hemolymph plasma. Furthermore, the infected S. exigua larvae induced transcription of several antimicrobial peptide (AMP) genes. Two entomopathogenic bacteria, Xenorhabdus nematophila (Xn) and Photorhabdus temperata subsp. temperata (Ptt), possessed specific PLA2-inhibitory activities and their culture broths significantly inhibited the enzyme activities in hemocytes, fat body, and plasma of S. exigua. In addition, the bacterial metabolites inhibited transcription of AMP genes in S. exigua that would normally respond to the immune challenge by N. rileyi. The immunosuppressive effect of Xn or Ptt bacterial broth resulted in significant enhancement of the fungal pathogenicity against late instar larvae of S. exigua and Plutella xylostella. The effect of such a mixture was confirmed by field assay against two lepidopteran species. These results suggest that the bacterial and fungal mixture can be applied to develop a novel biopesticide to control lepidopteran species.

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References

  • Anderson, S.O. 1979. Biochemistry of insect cuticle. Annu. Rev. Entomol. 24, 29–61.

    Article  Google Scholar 

  • Boucias, D.G., Schoborg, E.A., and Allen, G.E. 1982. The relative susceptibility of six noctuid species to infection by Nomuraea rileyi isolated from Anticarsia gemmatalis. J. Invertebr. Pathol. 39, 238–240.

    Article  Google Scholar 

  • Burke, J.E. and Dennis, E.A. 2009. Phospholipase A2 structure/function, mechanism and signaling. J. Lipid Res. 50, S237–S242.

    Article  PubMed  Google Scholar 

  • Chengxiang, H., Guangxing, Q., Ting, L., Xinglin, M., Rui, Z., Pan, Z., Zhongyuan, S., and Xijie, G. 2011. Differential gene expression in silkworm in response to Beauveria bassiana infection. Gene 484, 35–41.

    Article  PubMed  Google Scholar 

  • Dean, P., Gadsden, J.C., Richards, E.H., Edwards, J.P., Charnley, A.K., and Reynolds, S.E. 2002. Modulation by eicosanoid biosynthesis inhibitors of immune responses by the insect Manduca sexta to the pathogenic fungus Metarhizium anisopliae. J. Invertebr. Pathol. 79, 93–101.

    Article  PubMed  CAS  Google Scholar 

  • Gillespie, J.P., Kanost, M.R., and Trenczek, T. 1997. Biological mediators of insect immunity. Annu. Rev. Entomol. 42, 611–643.

    Article  PubMed  CAS  Google Scholar 

  • Goh, H.G., Lee, S.G., Lee, B.P., Choi, K.M., and Kim, J.H. 1990. Simple mass-rearing of beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae), on an artificial diet. Kor. J. Appl. Entomol. 29, 180–183.

    Google Scholar 

  • Hoffmann, J.A. 2003. The immune response of Drosophila. Nature 426, 33–38.

    Article  PubMed  CAS  Google Scholar 

  • Hwang, J. 2011. Transcriptional control of humoral immune responses in the beet armyworm, Spodoptera exigua. MS thesis. Andong National University, Andong, Republic of Korea.

    Google Scholar 

  • Ignoffo, C.M. 1981. The fungus Nomuraea rileyi as a microbial insecticide: fungi, pp. 513–538. In Burges, H.D. (ed.), Microbial Control of Pests and Plant Disease 1970–1980, Academic Press, London, UK.

    Google Scholar 

  • Ji, D., Yi, Y., Kang, G.H., Choi, Y.H., Kim, P., Baek, N.I., and Kim, Y. 2005. Identification of an antibacterial compound, benzylideneacetone, from Xenorhabdus nematophila against major plant-pathogenic bacteria. FEMS Microbiol. Lett. 239, 241–248.

    Article  Google Scholar 

  • Kawakami, K. 1972. Relationship between the pathogenic patches on the integument and the fungal reproduction in the muscardine-inoculated larvae of the silkworm, Bombyx mori L. J. Seric. Sci. Jpn. 41, 144–149.

    Google Scholar 

  • Kim, Y., Ji, D., Cho, S., and Park, Y. 2005. Two groups of entomopathogenic bacteria, Photorhabdus and Xenorhabdus, share an inhibitory action against phospholipase A2 to induce host immunodepression. Arch. Insect Biochem. Physiol. 59, 230–244.

    Article  PubMed  CAS  Google Scholar 

  • Kim, J. and Kim, Y. 2011. Three metabolites from an entomopathogenic bacterium, Xenorhabdus nematophila, inhibit larval development of Spodoptera exigua (Lepidoptera: Noctuidae) by inhibiting a digestive enzyme, phospholipase A2. Insect Sci. 18, 282–288.

    Article  CAS  Google Scholar 

  • Kosir, J.M., MacPherson, J.M., and Khachatourians, G.G. 1991. Genomic analysis of a virulent and a less virulent strain of the entomopathogenic fungus, Beauveria bassiana using restriction fragment length polymorphisms. Can. J. Microbiol. 37, 534–541.

    Article  PubMed  CAS  Google Scholar 

  • Kumar, V., Singh, G.P., Kumar, V., Babu, A.M., and Datta, R.K. 1997. SEM study on the invasion of Nomuraea rileyi (Farlow) on silkworm, Bombyx mori Linn. causing green muscardine. Mycopathologia 138, 141–144.

    Article  Google Scholar 

  • Kwon, B. and Kim, Y. 2008. Benzylideneacetone, an immunosuppressant, enhances virulence of Bacillus thuringiensis against beet armyworm (Lepidoptera: Noctuidae). J. Econ. Entomol. 101, 36–41.

    Article  PubMed  CAS  Google Scholar 

  • Leclerc, V. and Reichhart, J.M. 2004. The immune response of Drosophila melanogaster. Immunol. Rev. 198, 58–71.

    Article  Google Scholar 

  • Lemaitre, B. and Hoffmann, J. 2007. The host defense of Drosophila melanogaster. Annu. Rev. Immunol. 25, 697–743.

    Article  PubMed  CAS  Google Scholar 

  • Lemaitre, B., Meister, M., Govind, S., Georgel, P., Steward, R., Reichhart, J.M., and Hoffmann, J.A. 1995. Functional analysis and regulation of nuclear import of dorsal during the immune response in Drosophila. EMBO J. 14, 536–545.

    PubMed  CAS  Google Scholar 

  • Lord, J.C., Anderson, S., and Stanley, D.W. 2002. Eicosanoids mediate Manduca sexta cellular response to the fungal pathogen Beauveria bassiana: a role for lipoxygenase pathway. Arch. Insect Biochem. Physiol. 51, 46–54.

    Article  PubMed  CAS  Google Scholar 

  • Michel, T., Reichhart, J.M., Hoffman, J.A., and Royet, J. 2001. Drosophila Toll is activated by Gram-positive bacteria through a circulating peptidoglycan recognition protein. Nature 414, 756–759.

    Article  PubMed  CAS  Google Scholar 

  • Morishima, I., Yamano, Y., Inoue, K., and Matsuo, N. 1997. Eicosanoids mediate induction of immune genes in the fat body of the silkworm, Bombyx mori. FEBS Lett. 419, 83–86.

    Article  PubMed  CAS  Google Scholar 

  • Noda, T., Meguri, T., Iimure, K., Ono, M., and Araki, T. 2011. Potential of D-erythro-C14-sphinosine as an adjuvant for a fungal pesticide of Nomuraea rileyi. Biosci. Biotechnol. Biochem. 75, 373–375.

    Article  PubMed  CAS  Google Scholar 

  • Noda, T., Ono, M., Iimure, K., and Araki, T. 2010a. Isolation of a bioactive substance from the silkworm (Bombyx mori Linnaeus) that accelerates the germination of the entomopathogenic fungus Nomuraea rileyi (Farlow) Samson. Biosci. Biotechnol. Biochem. 74, 563–568.

    Article  PubMed  CAS  Google Scholar 

  • Noda, T., Ono, M., Iimure, K., and Araki, T. 2010b. Characterization of a germination-accelerating factor from the silkworm (Bombyx mori Linnaeus) of entomopathogenic fungus Nomuraea rileyi (Farlow) Samson. Biosci. Biotechnol. Biochem. 74, 1226–1230.

    Article  PubMed  CAS  Google Scholar 

  • Park, J. and Kim, Y. 2011. Benzylideneacetone suppresses both cellular and humoral immune responses of Spodoptera exigua and enhances fungal pathogenicity. J. Asia Pac. Entomol. 14, 423–427.

    Article  CAS  Google Scholar 

  • Pedrini, N., Crespo, R., and Juárez, M.P. 2007. Biochemistry of insect epicuticle degradation by entomopathogenic fungi. Comp. Biochem. Physiol. C 146, 124–137.

    Article  Google Scholar 

  • Pendland, J.C. and Boucias, D.G. 1985. Hemagglutinin activity in the hemolymph of Anticarsia gemmatalis larvae infected with the fungus Nomuraea rileyi. Dev. Comp. Immunol. 9, 21–30.

    Article  PubMed  CAS  Google Scholar 

  • Pendland, J.C. and Boucias, D.G. 2000. Comparative analysis of the binding of antibodies prepared against the insect Spodoptera exigua and against the mycopathogen Nomuraea rileyi. J. Invertebr. Pathol. 75, 107–116.

    Article  PubMed  CAS  Google Scholar 

  • Qin, L., Liu, X., Li, J., Chen, H., Yan, Q., Yang, Z.Y., Wang, L., and Chen, K. 2009. Protein profile of Nomuraea rileyi spore isolated from infected silkworm. Curr. Microbiol. 58, 578–595.

    Article  PubMed  CAS  Google Scholar 

  • Radvanyi, F., Jordan, L., Russo-Marie, F., and Bon, C. 1989. A sensitive and continuous fluorometric assay for phospholipase A2 using pyrene-labeled phospholipids in the presence of serum albumin. Anal. Biochem. 177, 103–109.

    Article  PubMed  CAS  Google Scholar 

  • SAS Institute, Inc. 1989. SAS/STAT User’s Guide, release 6.03 ed. SAS Institute, Cary, NC.

    Google Scholar 

  • Seo, S., Jang, H., Kim, K., and Kim, Y. 2010. Comparative analysis of immunosuppressive metabolites synthesized by an entomopathogenic bacterium, Photorhabdus temperata ssp. temperata, to select economic bacterial culture media. Kor. J. Appl. Entomol. 49, 409–416.

    Article  Google Scholar 

  • Shah, P.A. and Pell, J.K. 2003. Entomopathogenic fungi as biological control agents. Appl. Microbiol. Biotechnol. 61, 413–423.

    PubMed  CAS  Google Scholar 

  • Shrestha, S. and Kim, Y. 2008. Eicosanoid mediates prophenoloxidase release from oenocytoids in the beet armyworm, Spodoptera exigua. Insect Biochem. Mol. Biol. 38, 99–112.

    Article  PubMed  CAS  Google Scholar 

  • Shrestha, S. and Kim, Y. 2009a. Oenocytoid cell lysis to release prophenoloxidase in induced by eicosanoid via protein kinase C. J. Asia Pac. Entomol. 12, 301–305.

    Article  CAS  Google Scholar 

  • Shrestha, S. and Kim, Y. 2009b. Various eicosanoids modulate the cellular and humoral immune responses of the beet armyworm, Spodoptera exigua. Biochem. Biophys. Biotech. 73, 2077–2084.

    Article  CAS  Google Scholar 

  • Shrestha, S. and Kim, Y. 2010. Activation of immune-associated phospholipase A2 is functionally linked to Toll/Imd signal pathways in the red flour beetle, Tribolium castaneum. Dev. Comp. Immunol. 34, 530–537.

    Article  PubMed  CAS  Google Scholar 

  • Shrestha, S., Park, Y., Stanley, D., and Kim, Y. 2010. Genes encoding phospholipase A2 mediate insect nodulation reactions to bacterial challenge. J. Insect Physiol. 56, 324–332.

    Article  PubMed  CAS  Google Scholar 

  • Stanley, D.W. 2005. Eicosanoids, pp. 307–339. In Gilbert, L.I., Iatrou, K., and Gill, S.S. (eds.), Comprehensive Insect Molecular Science, Vol. 4, Elsevier, Amsterdam, Netherlands.

    Google Scholar 

  • Stanley, D.W. 2011. Eicosanoids: progress towards manipulating insect immunity. J. Appl. Entomol. 135, 534–545.

    Article  CAS  Google Scholar 

  • Strand, M.R. 2008. Insect hemocytes and their role in immunity, pp. 25–47. In Beckage, N.E. (ed.), Insect Immunology, Academic Press, New York, N.Y., USA.

    Google Scholar 

  • Supakdamrongkul, P., Bhumiratana, A., and Wiwat, C. 2010. Characterization of an extracellular lipase from the biocontrol fungus, Nomuraea rileyi MJ, and its toxicity toward Spodoptera litura. J. Invertebr. Pathol. 105, 228–235.

    Article  PubMed  CAS  Google Scholar 

  • Tanji, T., Hu, X., Weber, A.N., and Ip, Y.T. 2007. Toll and IMD pathway synergistically activate an innate immune response in Drosophila melanogaster. Mol. Cell Biol. 27, 4578–4588.

    Article  PubMed  CAS  Google Scholar 

  • Tanji, T. and Ip, Y.T. 2005. Regulators of the Toll and Imd pathways in the Drosophila innate immune response. Trends Immunol. 26, 193–198.

    Article  PubMed  CAS  Google Scholar 

  • Tunaz, H. 2006. Eicosanoid biosynthesis inhibitors influence mortality of Pieris brassicae larvae co-injected with fungal conidia. Arch. Insect Biochem. Physiol. 63, 93–100.

    Article  PubMed  CAS  Google Scholar 

  • Tunaz, H., Park, Y., Büyükgüzel, K., Bedick, J.C., Nor Aliza, A.R., and Stanley, D.W. 2003. Eicosanoids in insect immunity: bacterial infection stimulates hemocytic phospholipase A2 activity in tobacco hornworms. Arch. Insect Biochem. Physiol. 52, 1–6.

    Article  PubMed  CAS  Google Scholar 

  • Wu, S., Zhang, X., Chen, X., Cao, P., Beerntsen, B.T., and Ling, E. 2010. BmToll9, an arthropod conservative Toll, is likely involved in the local gut immune response in the silkworm, Bombyx mori. Dev. Comp. Immunol. 34, 93–96.

    Article  PubMed  CAS  Google Scholar 

  • Yajima, M., Tanaka, M., Tanahashi, N., Kikuchi, H., Natori, S., Oshima, Y., and Kurata, S. 2003. A newly established in vitro culture using transgenic Drosophila reveals functional coupling between the phospholipase A2-generated fatty acid cascade and lipopolysaccharide-dependent activation of the immune deficiency (imd) pathway in insect immunity. Biochem. J. 371, 205–210.

    Article  PubMed  CAS  Google Scholar 

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Park, JA., Kim, Y. Phospholipase A2 inhibitors in bacterial culture broth enhance pathogenicity of a fungus Nomuraea rileyi . J Microbiol. 50, 644–651 (2012). https://doi.org/10.1007/s12275-012-2108-3

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