嗜酸乳杆菌细胞壁提取物对致病性大肠杆菌粘附鸡肠纹状缘膜的影响

Effect of cell wall extracts from Lactobacillus acidophilus on pathogenic E.coli O78 binding to chicken intestinal brush border membranes

为研究嗜酸乳杆菌细胞壁提取物对致病性大肠杆菌(E.coli)粘附鸡肠纹状缘膜的影响,本实验以雏鸡小肠纹状缘膜为模型,以嗜酸乳杆菌和鸡致病性E.coli O78为研究对象,提取嗜酸乳杆菌表层蛋白、肽聚糖及E.coli O78菌毛,雏鸡小肠纹状缘膜,采用固相粘附试验和生物素标记法从分子间相互作用的关系评价了嗜酸乳杆菌细胞壁提取物对菌毛粘附的抑制作用,结果表明:表层蛋白和肽聚糖对菌毛粘附具有明显的抑制作用,呈浓度依赖性抑制菌毛与纹状缘膜的结合,具有竞争性拮抗作用,这主要是由空间占位造成的。肽聚糖的抑制作用相对较小。

To evaluate the effect of cell wall extracts from Lactobacillus acidophilus on inhibition of chicken pathogenic E.coli O78 binding to chicken intestinal brush border membrane.We used chicken intestinal brush border membrane treated as a model for the experiment.The activities of surfaces layer proteins,and whole peptidoglycan（WPG） from L.acidophilus were tested for inhibition of fimbriae-mediated adhesion of E.coli to chicken intestinal brush border membrane by solid phase binding and binding inhibition assay.The result showed that both S-layer proteins and WPG of L.acidophilus were able to inhibit the binding of fimbriae with brush border membrane in a dose-dependent manner,which indicated that the mechanism of antagonistic action might be based mainly on space occupancy and competitive binding.Of which the effect of S-layer proteins was stronger than that of WPG.