Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia in Katowice, Jagiellońska 28, 40-032 Katowice, Poland.
Int J Mol Sci. 2022 Dec 8;23(24):15561. doi: 10.3390/ijms232415561.
Fungal phytopathogens are challenging to control due to their penetration into plant tissues. Therefore, plant-colonizing bacteria could serve as an excellent weapon in fighting fungal infections. In this study, we aim to determine the biocontrol potential of the new endophytic strain KP32, isolated from the roots of L.; identify the related mechanisms; and understand the basis of its antagonistic interaction with taxonomically diverse fungi at the molecular level. The KP32 strain presented biological activity against , , , and , and its ability to inhibit the growth of the phytopathogens was found to be mediated by a broad spectrum of biocontrol features, such as the production of a number of lytic enzymes (amylases, chitinases, and proteases), siderophores, volatile organic and inorganic compounds, salicylic acid, and N-acyl-homoserine lactones. The higher expression of chitinase () and genes involved in the biosynthesis of hydrogen cyanide (), enterobactin (), and acetoin () in bacteria exposed to fungal filtrates confirmed that these factors could act in combination, leading to a synergistic inhibitory effect of the strain against phytopathogens. We also confirm the active movement, self-aggregation, exopolysaccharide production, and biofilm formation abilities of the KP32 strain, which are essential for effective plant colonization. Its biological activity and colonization potential indicate that KP32 holds tremendous potential for use as an active biopesticide and plant growth promoter.
真菌植物病原体因其能渗透入植物组织而难以控制。因此，定殖于植物的细菌可以成为防治真菌感染的有力武器。在本研究中，我们旨在确定从 L. 根部分离出的新内生菌株 KP32 的生防潜力；鉴定相关机制；并从分子水平上了解其与分类多样化真菌拮抗相互作用的基础。KP32 菌株对 、 、 、 和 具有生物活性，其抑制植物病原体生长的能力是由多种生防特征介导的，如产生多种裂解酶（淀粉酶、几丁质酶和蛋白酶）、铁载体、挥发性有机和无机化合物、水杨酸和 N-酰基高丝氨酸内酯。暴露于真菌滤液中的细菌中几丁质酶 () 和参与氰化氢 ()、肠杆菌素 () 和乙酰醇 () 生物合成的基因的更高表达证实，这些因素可以共同作用，导致该菌株对植物病原体产生协同抑制作用。我们还证实了 KP32 菌株的主动运动、自聚集、胞外多糖产生和生物膜形成能力，这些能力对于有效定殖植物至关重要。其生物活性和定殖潜力表明 KP32 具有作为活性生物农药和植物生长促进剂的巨大潜力。
