The aim of the study was to reveal the effects of ethanol stress on the production of epsilon-poly-l-lysine (ε-PL) in Streptomyces albulus X-18. The results showed that biomass and the utilization of glucose were respectively increased by ethanol stress. The ε-PL yield was increased by 41.42 % in the shake flask and 37.02 % in 10 L fermenter with 1% (v/v) ethanol. The morphology of colonies and mycelia showed significant differences. The intracellular reactive oxygen species level was increased by about 100 %. The ratio of unsaturated fatty acids to saturated fatty acids in the cell membrane was increased by ethanol stress. Isobaric Tags for Relative and Absolute Quantitation (iTRAQ) proteomic profile showed that 265 identified proteins were differentially expressed. The differentially expressed proteins (DEPs) were mainly involved in biological processes. The up-regulated DEPs were mainly involved in the redox reaction and stress response. The metabolic flux of l-Asp was shifted to l-Lys biosynthesis, and the DAP pathway was strengthened. Protein-protein interaction analysis showed that 30 DEPs interacted with l-Lys biosynthesis. The changes of ten proteins by Parallel Reaction Monitoring (PRM) were consistent with those by iTRAQ. The study provided valuable clues to better understand the mechanism of ε-PL biosynthesis improvement by ethanol stress.

该研究的目的是揭示乙醇胁迫对Streptomyces albulus中 epsilon-poly- l - lysine (ε-PL)产生的影响X-18。结果表明，乙醇胁迫分别增加了生物量和葡萄糖的利用。ε-PL 产量在摇瓶中增加了 41.42%，在 10 L 发酵罐中增加了 37.02%，乙醇为 1% (v/v)。菌落和菌丝体的形态表现出显着差异。细胞内活性氧水平增加了约 100%。乙醇胁迫增加了细胞膜中不饱和脂肪酸与饱和脂肪酸的比例。用于相对和绝对定量 (iTRAQ) 蛋白质组学特征的等压标签显示 265 种鉴定的蛋白质存在差异表达。差异表达蛋白（DEPs）主要参与生物过程。上调的 DEPs 主要参与氧化还原反应和应激反应。的代谢通量l -Asp 转变为l -Lys 生物合成，DAP 途径得到加强。蛋白质-蛋白质相互作用分析表明，30 个 DEP 与l- Lys 生物合成相互作用。Parallel Reaction Monitoring (PRM) 测得的 10 种蛋白质的变化与 iTRAQ 测得的一致。该研究为更好地理解乙醇胁迫改善 ε-PL 生物合成的机制提供了有价值的线索。