Chamoun Rony, Aliferis Konstantinos A, Jabaji Suha
Department of Plant Science, McGill University Sainte-Anne-de-Bellevue, QC, Canada.
Front Microbiol. 2015 Apr 29;6:353. doi: 10.3389/fmicb.2015.00353. eCollection 2015.
Stachybotrys elegans is able to parasitize the fungal plant pathogen Rhizoctonia solani AG-3 following a complex and intimate interaction, which, among others, includes the production of cell wall-degrading enzymes, intracellular colonization, and expression of pathogenic process encoding genes. However, information on the metabolome level is non-existent during mycoparasitism. Here, we performed a direct-infusion mass spectrometry (DIMS) metabolomics analysis using an LTQ Orbitrap analyzer in order to detect changes in the profiles of induced secondary metabolites of both partners during this mycoparasitic interaction 4 and 5 days following its establishment. The diketopiperazine(s) (DKPs) cyclo(S-Pro-S-Leu)/cyclo(S-Pro-S-Ile), ethyl 2-phenylacetate, and 3-nitro-4-hydroxybenzoic acid were detected as the primary response of Rhizoctonia 4 days following dual-culturing with Stachybotrys, whereas only the latter metabolite was up-regulated 1 day later. On the other hand, trichothecenes and atranones were mycoparasite-derived metabolites identified during mycoparasitism 4 and 5 days following dual-culturing. All the above secondary metabolites are known to exhibit bioactivity, including fungitoxicity, and represent key elements that determine the outcome of the interaction being studied. Results could be further exploited in programs for the evaluation of the bioactivity of these metabolites per se or their chemical analogs, and/or genetic engineering programs to obtain more efficient mycoparasite strains with improved efficacy and toxicological profiles.
优雅葡萄穗霉能够在经历复杂而密切的相互作用后寄生于真菌植物病原体立枯丝核菌AG-3，这种相互作用包括产生细胞壁降解酶、细胞内定殖以及致病过程编码基因的表达等。然而，关于菌寄生过程中代谢组水平的信息尚不存在。在此，我们使用LTQ Orbitrap分析仪进行了直接进样质谱（DIMS）代谢组学分析，以检测在这种菌寄生相互作用建立后4天和5天，双方诱导次生代谢产物谱的变化。在与优雅葡萄穗霉共培养4天后，二酮哌嗪（DKPs）环（S-脯氨酸-S-亮氨酸）/环（S-脯氨酸-S-异亮氨酸）、苯乙酸乙酯和3-硝基-4-羟基苯甲酸被检测为立枯丝核菌的主要反应产物，而仅后一种代谢产物在1天后上调。另一方面，单端孢霉烯族毒素和阿托酮是在共培养4天和5天的菌寄生过程中鉴定出的寄生物源代谢产物。已知上述所有次生代谢产物均具有生物活性，包括真菌毒性，并且是决定所研究相互作用结果的关键因素。这些结果可在评估这些代谢产物本身或其化学类似物的生物活性的项目中，和/或在基因工程项目中进一步加以利用，以获得具有更高效力和更优毒理学特征的更高效菌寄生菌株。
