三硫烷二丁烯酸对金黄色葡萄球菌抑菌的研究

Antimicrobial Mechanism of (2E, 2E)-4,4-trisulfanediylbis(but-2-enoic acid) against Staphylococcus aureus

摘要:

本文研究一种新型化合物三硫烷二丁烯酸(2E, 2E)-4,4-trisulfanediylbis(but-2-enoic acid)（TSDB）对食品中常见金黄色葡萄球菌的抑菌机理。通过蛋白质十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）法，观察在TSDB作用下菌体蛋白质的变化；高效液相色谱测定有机酸变化；AnnexinV单染色法观察细胞凋亡情况。结果表明：TSDB处理后金黄色葡萄球菌胞内蛋白质44.3~200 ku之间的条带变模糊或消失；菌体胞内苹果酸、柠檬酸含量均显著减少(分别平均下降了65.16%、56.18%)（p<0.05），而草酸和乳酸未检测到相对于空白对照组；细胞凋亡时，细胞膜内侧的磷脂酰丝氨酸外翻到细胞表面，与带有绿色荧光探针FITC的AnnexinV高度结合，使菌体细胞呈苹果绿。结论：TSDB处理后造成菌体细胞膜通透性改变，引起细胞有机酸代谢紊乱，抑制蛋白质合成，从而导致细胞凋亡或坏死。这一研究发现对开发食品防腐剂具有指导意义。

Abstract:

The antibacterial mechanism of a novel compound (2E, 2E)-4,4-trisulfanediylbis -(but-2-enoic acid) (TSDB) against Staphylococcus aureus in foods was investigated in this study. The changes of bacterial protein, organic acids, and bacteria cell apoptosis were evaluated by SDS-PAGE, HPLC, and AnnexinV, respectively. The results suggested that bacterial protein in Staphylococcus aureus between 44.3 and 200 ku became blurred or disappeared with TSDB treatment The content of intracellular malic acid and citric acid significantly decreased by 65.16%and 56.18%, respectively.(p<0.05), while oxalic acid and lactic acid were not detectable. Phosphatidylserine on the inside of spoilage bacteria turned tocell surface when the cells apoptosised, which integrated with AnnexinV with a green fluorescent probe FITC, and then leaded the bacterial cells to be apple green. In conclusion, cell membranes permeability changes, organic acid metabolism disorders, and the synthesis of proteins are inhibited after the treatment with TSDB, which lead apoptosis or necrosis. Therefore, it plays an important significance for food preservatives development.