Bacterial leaf blight, caused by pv. (), poses a significant threat to rice cultivation across diverse regions. Growing concerns about pesticide resistance and environmental impact underscore the urgent necessity for eco-friendly biopesticides. Here, the complete genome sequence of strain ML27 revealed substantial antimicrobial activity and secondary metabolite production potential through genome mining. 3,4-dimethoxyphenol (purity 97%) was successfully isolated from the fermentation broth of strain ML27, exhibiting broad and pronounced inhibitory effects on the growth of seven different fungi and five tested bacteria. The efficacy of 3,4-dimethoxyphenol in controlling rice bacterial leaf blight was evaluated through pot tests, demonstrating substantial therapeutic (69.39%) and protective (84.53%) effects. Application of 3,4-dimethoxyphenol to resulted in cells displayed notable surface depressions, wrinkles, distortions, or even ruptures compared to their typical morphology. Transcriptome analysis revealed significant inhibition of membrane structures, protein synthesis and secretion, bacterial secretion system, two-component system, flagellar assembly, as well as various metabolic and biosynthetic pathways by 3,4-dimethoxyphenol. Notably, the down-regulation of the type III secretion system (T3SS) expression was a pivotal finding. Furthermore, validation via quantitative real-time polymerase chain reaction (qRT-PCR) analysis confirmed significant downregulation of 10 genes related to T3SS upon 3,4-dimethoxyphenol treatment. Based on these results, it is promising to develop 3,4-dimethoxyphenol as a novel biopesticide targeting the T3SS of for controlling bacterial leaf blight in rice.

中文翻译：

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转录组分析揭示了白黄链霉菌 ML27 菌株中 3,4-二甲氧基苯酚对米黄单胞菌 pv. 的抑制机制。米霉


细菌性叶枯病，由光伏引起。 ()，对不同地区的水稻种植构成重大威胁。人们对农药耐药性和环境影响的日益担忧凸显了对生态友好型生物农药的迫切需要。在这里，菌株 ML27 的完整基因组序列通过基因组挖掘揭示了显着的抗菌活性和次级代谢产物生产潜力。从菌株ML27的发酵液中成功分离出3,4-二甲氧基苯酚（纯度97%），对七种不同的真菌和五种测试细菌的生长表现出广泛而显着的抑制作用。通过盆栽试验评估了3,4-二甲氧基苯酚防治水稻白叶枯病的效果，显示出显着的治疗作用（69.39%）和保护作用（84.53%）。与典型形态相比，使用3,4-二甲氧基苯酚导致细胞表现出明显的表面凹陷、皱纹、扭曲，甚至破裂。转录组分析显示，3,4-二甲氧基苯酚对膜结构、蛋白质合成和分泌、细菌分泌系统、双组分系统、鞭毛组装以及各种代谢和生物合成途径有显着抑制作用。值得注意的是，III 型分泌系统（T3SS）表达的下调是一个关键发现。此外，通过定量实时聚合酶链式反应 (qRT-PCR) 分析进行的验证证实，在 3,4-二甲氧基苯酚处理后，与 T3SS 相关的 10 个基因显着下调。基于这些结果，开发3,4-二甲氧基苯酚作为一种针对T3SS的新型生物农药有望用于防治水稻白叶枯病。