Yan Yi, Wang Jueyu, Zhao Na, Cui Daizong, Zhao Min
College of Life Science, Northeast Forestry University, Harbin 150040, China.
Key Laboratory for Enzyme and Enzyme-like Material Engineering of Heilongjiang, Harbin 150040, China.
Microorganisms. 2025 Apr 21;13(4):953. doi: 10.3390/microorganisms13040953.
pv. () is a biotrophic bacterial pathogen, which causes devastating bacterial blight disease worldwide. In this study, we thoroughly investigated the antimicrobial effect of the plant-derived extract chelerythrine against pv. () and elucidated its mechanism. Chelerythrine is a quaternary ammonium alkaloid with a 2,3,7,8-tetrasubstituted phenanthridine structure, extracted from plants, such as the whole plant of Chelidonium majus, and the roots, stems, and leaves of Macleaya cordata. We found that chelerythrine significantly inhibited the growth of at a concentration of 1.25 μg/mL. Further experiments revealed that chelerythrine interfered with the division and reproduction of the bacterium, leading to its filamentous growth. Additionally, it increased the permeability of cell membranes and effectively decreased the pathogenicity of , including the inhibition of extracellular polysaccharide production, cellulase secretion, and biofilm formation. Chelerythrine induced the accumulation of reactive oxygen species in the bacterium, triggering oxidative stress. The result showed that chelerythrine inhibited the formation of the Z-ring of , interfered with the synthesis of pyrimidine and purine nucleotides, inhibited DNA damage repair, and inhibited the formation of peptidoglycan and lipid-like A, thus interfering with cell membrane permeability, inhibiting carbohydrate metabolism and phosphorylation of sugars, reducing pathogenicity, and ultimately inhibiting bacterial growth and leading to the destruction or lysis of bacterial cells. Altogether, our results suggest that the antimicrobial effect of chelerythrine on exhibits multi-target properties. Additionally, its effective inhibitory concentration is low. These findings provide a crucial theoretical basis and guidance for the development of novel and efficient plant-derived antimicrobial compounds.
稻瘟病菌（Magnaporthe oryzae）是一种活体营养型细菌病原体，在全球范围内引发毁灭性的稻瘟病。在本研究中，我们深入研究了植物源提取物白屈菜红碱对稻瘟病菌（Magnaporthe oryzae）的抗菌作用并阐明了其作用机制。白屈菜红碱是一种具有2,3,7,8-四取代菲啶结构的季铵生物碱，从植物中提取，如白屈菜的全株以及博落回的根、茎和叶。我们发现白屈菜红碱在浓度为1.25μg/mL时能显著抑制稻瘟病菌（Magnaporthe oryzae）的生长。进一步实验表明，白屈菜红碱干扰了该细菌的分裂和繁殖，导致其丝状生长。此外，它增加了稻瘟病菌（Magnaporthe oryzae）细胞膜的通透性，并有效降低了稻瘟病菌（Magnaporthe oryzae）的致病性，包括抑制细胞外多糖的产生、纤维素酶的分泌和生物膜的形成。白屈菜红碱诱导细菌中活性氧的积累，引发氧化应激。结果表明，白屈菜红碱抑制了稻瘟病菌（Magnaporthe oryzae）Z环的形成，干扰了嘧啶和嘌呤核苷酸的合成，抑制了DNA损伤修复，并抑制了肽聚糖和类脂A的形成，从而干扰细胞膜通透性，抑制碳水化合物代谢和糖的磷酸化，降低致病性，最终抑制细菌生长并导致细菌细胞的破坏或裂解。总之，我们的结果表明白屈菜红碱对稻瘟病菌（Magnaporthe oryzae）的抗菌作用具有多靶点特性。此外，其有效抑制浓度较低。这些发现为新型高效植物源抗菌化合物的开发提供了关键的理论基础和指导。
