Douka Dimitra, Spantidos Tasos-Nektarios, Tsalgatidou Polina C, Katinakis Panagiotis, Venieraki Anastasia
Laboratory of General and Agricultural Microbiology, Department of Crop Science, Agricultural University of Athens, Iera Odos 75, 11855 Athens, Greece.
Department of Agriculture, University of the Peloponnese, 24150 Kalamata, Greece.
Microorganisms. 2024 Dec 16;12(12):2604. doi: 10.3390/microorganisms12122604.
Endophytic microbes in medicinal plants often possess beneficial traits for plant health. This study focuses on the bacterial endophyte strain B.L.Ns.14, isolated from leaves, which demonstrated multiple plant growth-promoting properties. In vitro tests showed that B.L.Ns.14 supports plant growth, colonization, and tolerance to abiotic stress. The strain also exhibited antifungal activity against phytopathogens such as , , , and f. sp. . Whole-genome analysis, supported by ANI and dDDH values, identified B.L.Ns.14 as . Genome mining revealed 128 active carbohydrate enzymes (Cazymes) related to endophytism and biocontrol functions, along with genes involved in phosphate solubilization, siderophore and IAA production, biofilm formation, and motility. Furthermore, genes for osmolyte metabolism, Na+/H+ antiporters, and stress response proteins were also identified. The genome harbors 12 secondary metabolite biosynthetic gene clusters, including those for surfactin, plipastatin mojavensin, rhizocticin A, and bacilysin, known for their antagonistic effects against fungi. Additionally, B.L.Ns.14 promoted growth under both normal and saline conditions, and enhanced growth via seed biopriming and root irrigation. These findings suggest that B.L.Ns.14 holds potential as a biocontrol and plant productivity agent, warranting further field testing.
药用植物中的内生微生物通常具有对植物健康有益的特性。本研究聚焦于从叶片中分离出的细菌内生菌株B.L.Ns.14，该菌株展现出多种促进植物生长的特性。体外试验表明，B.L.Ns.14有助于植物生长、定殖以及对非生物胁迫的耐受性。该菌株还对诸如、、、和f. sp. 等植物病原体表现出抗真菌活性。基于ANI和dDDH值支持的全基因组分析将B.L.Ns.14鉴定为。基因组挖掘揭示了128种与内生作用和生物防治功能相关的活性碳水化合物酶（糖基水解酶），以及参与磷溶解、铁载体和吲哚-3-乙酸（IAA）产生、生物膜形成和运动性的基因。此外，还鉴定出了渗透调节物质代谢、Na+/H+反向转运蛋白和应激反应蛋白的基因。该基因组含有12个次生代谢物生物合成基因簇，包括那些对真菌具有拮抗作用的表面活性素、丰原素、莫哈韦菌素、根霉素A和杆菌溶素的基因簇。此外，B.L.Ns.14在正常和盐胁迫条件下均促进了生长，并通过种子生物引发和根部灌溉增强了生长。这些发现表明，B.L.Ns.14具有作为生物防治剂和提高植物生产力制剂的潜力，值得进一步进行田间试验。
