Advanced Agriecological Research Sdn. Bhd., Kota Damansara, Petaling Jaya, Selangor, Malaysia.
Metabolomics Research Laboratory, Institute of Systems Biology (INBIOSIS), Universiti Kebangsaan Malaysia (UKM), Bangi, Selangor, Malaysia.
PLoS One. 2021 Dec 31;16(12):e0262029. doi: 10.1371/journal.pone.0262029. eCollection 2021.
Various phenolic compounds have been screened against Ganoderma boninense, the fungal pathogen causing basal stem rot in oil palms. In this study, we focused on the effects of salicylic acid (SA) on the growth of three G. boninense isolates with different levels of aggressiveness. In addition, study on untargeted metabolite profiling was conducted to investigate the metabolomic responses of G. boninense towards salicylic acid. The inhibitory effects of salicylic acid were both concentration- (P < 0.001) and isolate-dependent (P < 0.001). Also, growth-promoting effect was observed in one of the isolates at low concentrations of salicylic acid where it could have been utilized by G. boninense as a source of carbon and energy. Besides, adaptation towards salicylic acid treatment was evident in this study for all isolates, particularly at high concentrations. In other words, inhibitory effect of salicylic acid treatment on the fungal growth declined over time. In terms of metabolomics response to salicylic acid treatment, G. boninense produced several metabolites such as coumarin and azatyrosine, which suggests that salicylic acid modulates the developmental switch in G. boninense towards the defense mode for its survival. Furthermore, the liquid chromatography time-of-flight mass spectrometry (LC-TOF-MS) analysis showed that the growth of G. boninense on potato dextrose agar involved at least four metabolic pathways: amino acid metabolism, lipid pathway, tryptophan pathway and phenylalanine pathway. Overall, there were 17 metabolites that contributed to treatment separation, each with P<0.005. The release of several antimicrobial metabolites such as eudistomin I may enhance G. boninense's competitiveness against other microorganisms during colonisation. Our findings demonstrated the metabolic versatility of G. boninense towards changes in carbon sources and stress factors. G. boninense was shown to be capable of responding to salicylic acid treatment by switching its developmental stage.
各种酚类化合物已被筛选用于对抗导致油棕基部腐烂的病原菌——胶孢炭疽菌。在本研究中，我们专注于水杨酸（SA）对三种具有不同侵袭力的胶孢炭疽菌分离株生长的影响。此外，还进行了非靶向代谢物谱分析，以研究胶孢炭疽菌对水杨酸的代谢组响应。水杨酸的抑制作用既依赖于浓度（P < 0.001），也依赖于分离株（P < 0.001）。此外，在水杨酸的低浓度下，观察到一种分离株的生长促进作用，这可能被胶孢炭疽菌用作碳和能源的来源。此外，在本研究中，所有分离株都表现出对水杨酸处理的适应性，特别是在高浓度下。换句话说，水杨酸处理对真菌生长的抑制作用随时间的推移而下降。就代谢组学对水杨酸处理的响应而言，胶孢炭疽菌产生了几种代谢物，如香豆素和氮酪氨酸，这表明水杨酸调节了胶孢炭疽菌向防御模式的发育转变，以维持其生存。此外，液相色谱飞行时间质谱（LC-TOF-MS）分析表明，胶孢炭疽菌在马铃薯葡萄糖琼脂上的生长至少涉及四个代谢途径：氨基酸代谢、脂质途径、色氨酸途径和苯丙氨酸途径。总的来说，有 17 种代谢物有助于处理分离，每种代谢物的 P 值均<0.005。几种抗菌代谢物的释放，如 eudistomin I，可能会增强胶孢炭疽菌在定植过程中对其他微生物的竞争力。我们的研究结果表明，胶孢炭疽菌在应对碳源和应激因素变化时具有代谢多样性。胶孢炭疽菌能够通过改变其发育阶段来应对水杨酸处理。
