【摘要】 研究亚油酸（linoleic acid,LA）诱导下植物乳杆菌（Lactobacillus plantarum）p-8的蛋白组和类组蛋白乙酰化水平差异，探究共轭亚油酸（conjugated linoleic acid,CLA）产生的机制。结果表明，LA的最佳诱导质量浓度为1 mg/mL，在此质量浓度条件下，蛋白质组学分析发现，烯酰-酰基载体蛋白还原酶、酰基载体蛋白等脂肪酸合成的关键蛋白因子下调，脂肪酸合成下调，乙酰基转移酶水平上调。Western blot结合体外添加NaAc实验表明，乙酰辅酶A含量增加导致类组蛋白乙酰化水平提升。实时聚合酶链式反应检测显示，添加LA和NaAc使CLA相关酶、转录调控因子和Sigma因子的mRNA表达升高，CLA含量也提高。相关性分析得出，乙酰辅酶A与LA水合酶转录水平和CLA含量之间呈显著正相关，揭示乙酰辅酶A和乙酰基转移酶含量上调导致类组蛋白乙酰化加强而上调CLA合成。结果为分子改良或科学调控乳酸菌以提高CLA转化率奠定了基础。更多还原

【Abstract】 In this study, changes in proteome and histone-like acetylation levels of Lactobacillus plantarum p-8 induced by linoleic acid(LA) were explored to investigate the mechanism of conjugated linoleic acid(CLA) production. The results showed that the optimal concentration of LA for inducing CLA production was 1 mg/mL. Proteomic analysis revealed that at this concentration, key protein factors for fatty acid synthesis such as enoyl acyl carrier protein(ACP) reductase and acyl carrier proteins were down-regulated, fatty acid synthesis was down-regulated, and acetyltransferase was up-regulated.Western blot showed that the increase in the content of acetyl-CoA upon NaAc addition resulted in elevated histonelike protein acetylation levels. The addition of LA and NaAc increased the mRNA expression of CLA-related enzymes,transcription factors(TF) and Sigma factors, as determined by real-time polymerase chain reaction(real-time PCR),and increased the transformation rate of CLA. Correlation analysis yielded a significant positive correlation between the transcriptional levels of acetyl-CoA and linoleic acid hydratase(CLA-hy) and the transformation rate of CLA, revealing that the up-regulation of acetyl-CoA and acetyltransferase contents led to enhanced histone-like acetylation and consequent up-regulation of CLA synthesis. These results provide a basis for molecular modification and scientific regulation of lactic acid bacteria to improve CLA conversion.更多还原