Dey Riddha, Devi Seema, Prasad Jay Kishor, Jangra Jatin, Kumar Rajnish, Raghuwanshi Richa
Department of Botany, Mahila Mahavidyalaya, Banaras Hindu University, Varanasi, Uttar Pradesh, 221005, India.
Department of Pharmaceutical Engineering and Technology, IIT(BHU), Varanasi, Uttar Pradesh, 221005, India.
World J Microbiol Biotechnol. 2025 Jun 25;41(7):204. doi: 10.1007/s11274-025-04451-2.
Endophytic bacteria reside asymptomatically inside host plant tissues and have the potential to protect the host plant from phytopathogens and enhance plant immunity. Exploration of the biocontrol mechanism of these beneficial bacteria can assure the development of eco-friendly pesticides for the effective management of phytopathogens. In our study, the isolated endophytic bacteria examined for its antimicrobial potential was identified as Pseudomonas gessardii strain RRBHU-1 based on 16 S rRNA gene sequence analysis. The crude extract containing the secondary metabolites from the P. gessardii strain RRBHU-1 demonstrated antagonistic activity against Xanthomonas vesicatoria, the causal organism of bacterial leaf spot disease in tomato plants. X. vesicatoria when treated with the RRBHU-1 extract showed disruption of the cell membrane, significant ROS production, and substantial antibiofilm activity. The extract separated through TLC and RP-HPLC and characterized using FT-IR, NMR, and HRAMS, and was identified as 4-Dodecylbenzene sulfonic acid (4-DBSA). This study is the first report on the presence of 4-DBSA in the Pseudomonas genera. In silico studies revealed stable interactions and high binding energies of 4-DBSA and the proteins directly involved in Xanthomonas virulence. This study suggests the possible utilization of P. gessardii strain RRBHU-1 as biopesticides against X. vesicatoria, encompassing sustainable agricultural practices.
内生细菌无症状地存在于宿主植物组织内部，具有保护宿主植物免受植物病原体侵害并增强植物免疫力的潜力。探索这些有益细菌的生物防治机制可以确保开发出生态友好型农药，以有效管理植物病原体。在我们的研究中，根据16S rRNA基因序列分析，对分离出的具有抗菌潜力的内生细菌进行鉴定，确定其为杰氏假单胞菌菌株RRBHU-1。来自杰氏假单胞菌菌株RRBHU-1的含有次生代谢产物的粗提物对番茄细菌性叶斑病的病原菌番茄疮痂病菌表现出拮抗活性。用RRBHU-1提取物处理的番茄疮痂病菌显示出细胞膜破坏、大量活性氧产生以及显著的抗生物膜活性。通过薄层色谱法（TLC）和反相高效液相色谱法（RP-HPLC）分离提取物，并使用傅里叶变换红外光谱（FT-IR）、核磁共振（NMR）和高分辨精确质量数质谱（HRAMS）进行表征，鉴定其为4-十二烷基苯磺酸（4-DBSA）。本研究是关于假单胞菌属中存在4-DBSA的首次报道。计算机模拟研究揭示了4-DBSA与直接参与番茄疮痂病菌毒力的蛋白质之间稳定的相互作用和高结合能。本研究表明，杰氏假单胞菌菌株RRBHU-1有可能作为针对番茄疮痂病菌的生物农药，这符合可持续农业实践。
