Table_1_Metabolomic profiles of the liquid state fermentation in co-culture of Eurotium amstelodami and Bacillus licheniformis.XLSX

As an important source of new drug molecules, secondary metabolites (SMs) produced by microorganisms possess important biological activities, such as antibacterial, anti-inflammatory, and hypoglycemic effects. However, the true potential of microbial synthesis of SMs has not been fully elucidated as the SM gene clusters remain silent under laboratory culture conditions. Herein, we evaluated the inhibitory effect of Staphylococcus aureus by co-culture of Eurotium amstelodami and three Bacillus species, including Bacillus licheniformis, Bacillus subtilis, and Bacillus amyloliquefaciens. In addition, a non-target approach based on ultra-performance liquid chromatography time-of-flight mass spectrometry (UPLC-TOF-MS) was used to detect differences in extracellular and intracellular metabolites. Notably, the co-culture of E. amstelodami and Bacillus spices significantly improved the inhibitory effect against S. aureus, with the combination of E. amstelodami and B. licheniformis showing best performance. Metabolomics data further revealed that the abundant SMs, such as Nummularine B, Lucidenic acid E2, Elatoside G, Aspergillic acid, 4-Hydroxycyclohexylcarboxylic acid, Copaene, and Pipecolic acid were significantly enhanced in co-culture. Intracellularly, the differential metabolites were involved in the metabolism of amino acids, nucleic acids, and glycerophospholipid. Overall, this work demonstrates that the co-culture strategy is beneficial for inducing biosynthesis of active metabolites in E. amstelodami and B. licheniformis.

作为新型药物分子的重要来源，微生物产生的次生代谢产物（SMs）蕴含着重要的生物活性，诸如抗菌、抗炎和降糖作用。然而，微生物合成SMs的真正潜力尚未得到充分阐明，因为SM基因簇在实验室培养条件下处于沉默状态。本研究评估了曲霉菌属的Eurotium amstelodami与三种芽孢杆菌（包括芽孢杆菌属的Bacillus licheniformis、Bacillus subtilis和Bacillus amyloliquefaciens）共培养对金黄色葡萄球菌的抑制作用。此外，采用基于超高效液相色谱-飞行时间质谱（UPLC-TOF-MS）的非靶向方法，检测了细胞外和细胞内代谢物的差异。值得注意的是，E. amstelodami与芽孢杆菌属的共培养显著增强了对抗S. aureus的抑制作用，其中E. amstelodami与B. licheniformis的组合表现最为优异。代谢组学数据进一步揭示了丰富的次生代谢产物，如Nummularine B、Lucidenic acid E2、Elatoside G、Aspergillic acid、4-Hydroxycyclohexylcarboxylic acid、Copaene和Pipecolic acid在共培养条件下显著增加。在细胞内，差异代谢物涉及氨基酸、核酸和甘油磷脂的代谢。总体而言，本研究证实了共培养策略对于诱导E. amstelodami和B. licheniformis中活性代谢物的生物合成具有益处。