College of Plant Protection, Hunan Agricultural University, Changsha 410128, China.
Institute of Plant Protection, Hunan Academy of Agricultural Sciences, Changsha 410125, China.
Genes (Basel). 2023 May 17;14(5):1096. doi: 10.3390/genes14051096.
Antimicrobial peptides (AMPs) from black solider flies (, BSF) exhibiting broad-spectrum antimicrobial activity are the most promising green substitutes for preventing the infection of phytopathogenic fungi; therefore, AMPs have been a focal topic of research. Recently, many studies have focused on the antibacterial activities of BSF AMPs against animal pathogens; however, currently, their antifungal activities against phytopathogenic fungi remain unclear. In this study, 7 AMPs selected from 34 predicted AMPs based on BSF metagenomics were artificially synthesized. When conidia from the hemibiotrophic phytopathogenic fungi and were treated with the selected AMPs, three selected AMPs-CAD1, CAD5, and CAD7-showed high appressorium formation inhibited by lengthened germ tubes. Additionally, the MIC concentrations of the inhibited appressorium formations were 40 μM, 43 μM, and 43 μM for M. oryzae, while 51 μM, 49 μM, and 44 μM were observed for , respectively. A tandem hybrid AMP named CAD-Con comprising CAD1, CAD5, and CAD7 significantly enhanced antifungal activities, and the MIC concentrations against and were 15 μM and 22 μM, respectively. In comparison with the wild type, they were both significantly reduced in terms of virulence when infection assays were performed using the treated conidia of or by CAD1, CAD5, CAD7, or CAD-Con. Meanwhile, their expression levels of CAD1, CAD5, and CAD7 could also be activated and significantly increased after the BSF larvae were treated with the conidia of or , respectively. To our knowledge, the antifungal activities of BSF AMPs against plant pathogenic fungi, which help us to seek potential AMPs with antifungal activities, provide proof of the effectiveness of green control strategies for crop production.
抗菌肽 (AMPs) 来源于黑黄赤眼蜂 (BSF)，具有广谱抗菌活性，是预防植物病原菌感染的最有前途的绿色替代品；因此，AMPs 一直是研究的焦点。最近，许多研究都集中在 BSF AMPs 对动物病原体的抗菌活性上；然而，目前它们对植物病原菌的抗真菌活性尚不清楚。在本研究中，根据 BSF 宏基因组学预测的 34 种 AMPs 中选择了 7 种 AMPs 进行人工合成。当半活体植物病原菌的分生孢子与所选 AMPs 一起处理时，3 种所选 AMPs-CAD1、CAD5 和 CAD7-表现出由延长的芽管引起的高附着胞形成抑制。此外，抑制附着胞形成的 MIC 浓度分别为 40 μM、43 μM 和 43 μM 用于 M. oryzae，而 51 μM、49 μM 和 44 μM 用于 ，分别。一种名为 CAD-Con 的串联杂交 AMP 由 CAD1、CAD5 和 CAD7 组成，显著增强了抗真菌活性，对 和 的 MIC 浓度分别为 15 μM 和 22 μM。与野生型相比，在用处理过的分生孢子感染时，它们的毒力都显著降低，CAD1、CAD5、CAD7 或 CAD-Con 分别用于 或 。同时，当 BSF 幼虫分别用 或 的分生孢子处理后，它们的 CAD1、CAD5 和 CAD7 的表达水平也可以被激活并显著增加。据我们所知，BSF AMPs 对植物病原菌的抗真菌活性有助于我们寻找具有抗真菌活性的潜在 AMPs，为作物生产提供了绿色控制策略的有效性证据。
