College of Food Science and Engineering, Northwest A & F University, Yangling 712100, China; XiZang Agriculture and Animal Husbandry College, Linzhi 860000, China.
College of Food Science and Engineering, Northwest A & F University, Yangling 712100, China.
Food Chem. 2018 Oct 30;264:377-385. doi: 10.1016/j.foodchem.2018.04.137. Epub 2018 May 2.
Oenococcus oeni (O. oeni) induces malolactic fermentation to improve wine quality. However, the molecular basis of mechanisms involved in its freeze-drying resistance remains unclear. In this work, O. oeni SD-2a without freeze-drying (No-FD), with freeze-drying (FD) and freeze-drying with monosodium glutamate (MSG) (FD-MSG) were investigated. Flow cytometry results showed severe cell damage in FD cells and less membrane transmissibility in FD-MSG cells. Meanwhile, extracellular polymeric substances (EPS) were detected in FD and FD-MSG cells by scanning electron microscopy. Bioinformatic analysis revealed that varying proteins were involved in carbon, lipid and nucleic acids metabolism, stress response, oxidoreductase activity and signal sensing. Among the identified proteins, the highlighted proteins were those involved in polysaccharides production and signal sensing for freeze-drying resistance and cyclopropane fatty acid metabolism for MSG addition.
酒酒球菌（Oenococcus oeni）能够诱导苹果酸-乳酸发酵，从而提高葡萄酒的质量。然而，其抗冻干机制的分子基础仍不清楚。在这项工作中，我们研究了未经冻干（No-FD）、经冻干（FD）和经冻干并添加谷氨酸单钠（FD-MSG）处理的酒酒球菌 SD-2a。流式细胞术的结果表明 FD 细胞的细胞膜严重受损，而 FD-MSG 细胞的细胞膜通透性较低。同时，扫描电子显微镜观察到 FD 和 FD-MSG 细胞中存在胞外聚合物（EPS）。生物信息学分析表明，不同的蛋白质参与了碳、脂类和核酸代谢、应激反应、氧化还原酶活性和信号感应。在鉴定出的蛋白质中，与多糖产生和冻干抗性信号感应以及添加谷氨酸单钠时的环丙烷脂肪酸代谢相关的蛋白质较为突出。
