乳酸杆菌S-层蛋白对产肠毒素大肠杆菌黏附Caco-2细胞的协同作用

摘要

设计3种黏附试验分别研究了嗜酸乳酸杆菌和S-层蛋白对产肠毒素大肠杆菌黏附Caco-2细胞的影响.结果显示:在置换试验中,嗜酸乳酸杆菌及S-层蛋白对产肠毒素大肠杆菌黏附Caco-2细胞没有影响;但在排斥试验和竞争试验中,嗜酸乳酸杆菌及S-层蛋白均对产肠毒素大肠杆菌黏附Caco-2细胞产生明显的协同作用,在排斥试验中嗜酸乳酸杆菌及S-层蛋白分别增加产肠毒素大肠杆菌的黏附数量 95.23%±4.22%(P<0.01)和 352.30%±2.26%(P<0.01),在竞争试验中分别增加 389.06%±3.35%(P<0.01)和 55.57%±5.81%(P<0.05);并且S-层蛋白在排斥试验中,对产肠毒素大肠杆菌的协同黏附作用大于竞争试验中的协同黏附作用.可见,乳酸杆菌对产肠毒素大肠杆菌的协同黏附作用关键在于S-层蛋白,S-层蛋白可能起到"连接桥"的作用.%Three adhesive experiments were designed to investigate the effects of Lactobacillus acidophilus and its S-layer proteins on the adhesion of enterotoxigenic E.coli to Caco-2 cells.The results showed that S-layer proteins exhibited strongly synergistic effect of adhesive properties of enterotoxigenic E.coli in the exclusive and competitive experiments but not in the displacement experiment.In the exclusive experiments, Lactobacillus acidophilus and its S-layer proteins increased the number of enterotoxigenic E.coli adhered to Caco-2 cells by 95.23%±4.22% (P<0.01) and 352.30%±2.26% (P<0.01).In the competitive experiments, Lactobacillus acidophilus and its S-layer proteins increased the number of enterotoxigenic E.coli adhered to Caco-2 cells by 389.06%±3.35% (P<0.01) and 55.57%±5.81% (P<0.05).Furthermore, the S-layer proteins showed a stronger effect in the exclusive experiment than that in the competitive experiment to increase enterotoxigenic E.coli adhesion to Caco-2 monolayers.The data indicat that S-layer proteins play a critical role on the synergistic effect of Lactobacillus acidophilus on the adherence ability of enterotoxigenic E.coli, which may be relative to the S-layer proteins-induced bridge.