Bipolaris sorokiniana is an important biotic constraint for global wheat production, causing spot blotch disease. In this work, we present a comprehensive characterization of the cell-free culture filtrate (CF) and precipitated fraction (PF) of Bacillus cabrialesii TE3^T showing an effective inhibition of spot blotch. Our results indicated that CF produced by B. cabrialesii TE3^T inhibits the growth of B. sorokiniana through stable metabolites (after autoclaving and proteinase K treatment). Antifungal metabolites in CF and PF were explored by an integrated genomic-metabolomic approach. Genome-mining revealed that strain TE3^T contains the biosynthetic potential to produce wide spectrum antifungal (surfactin, fengycin, and rhizocticin A) and antibacterial metabolites (bacillaene, bacilysin, bacillibactin, and subtilosin A), and through bioactivity-guided LC-ESI-MS/MS approach we determined that a lipopeptide complex of surfactin and fengycin homologs was responsible for antifungal activity exhibited by B. cabrialesii TE3^T against the studied phytopathogen. In addition, our results demonstrate that i) a lipopeptide complex inhibits B. sorokiniana by disrupting its cytoplasmatic membrane and ii) reduced spot blotch disease by 93 %. These findings show the potential application of metabolites produced by strain TE3^T against B. sorokiniana and provide the first insight into antifungal metabolites produced by the novel Bacillus species, Bacillus cabrialesii.

Bipolaris sorokiniana是全球小麦生产的重要生物制约因素，会导致斑点病。在这项工作中，我们对卡氏芽孢杆菌TE3 ^T的无细胞培养滤液 (CF) 和沉淀部分 (PF) 进行了全面表征，显示出对斑点斑点的有效抑制。我们的结果表明，CF产生由B. cabrialesii TE3 ^Ť抑制生长B. sorokiniana（高压灭菌后和蛋白酶K处理）通过稳定代谢物。通过综合基因组代谢组学方法探索了 CF 和 PF 中的抗真菌代谢物。基因组挖掘显示菌株 TE3 ^T含有产生广谱抗真菌剂（表面活性素、芬奇素和根瘤菌素 A）和抗菌代谢物（芽孢杆菌素、芽孢杆菌素、芽孢杆菌素和枯草杆菌素 A）的生物合成潜力，并且通过生物活性引导的 LC-ESI-MS/MS 方法，我们确定了Surfactin和 fengycin 同源物的脂肽复合物负责B. cabrialesii TE3 ^T对所研究的植物病原体表现出的抗真菌活性。此外，我们的结果表明，i) 脂肽复合物通过破坏B. sorokiniana的细胞质膜来抑制B. sorokiniana，并且 ii) 将斑点斑点病减少了 93%。这些发现显示了菌株 TE3 ^T产生的代谢物对B. sorokiniana的潜在应用并首次深入了解新型芽孢杆菌菌种Bacillus cabrialesii产生的抗真菌代谢物。