甘露二糖分子构型对鸡源致病性大肠杆菌凝聚酵母细胞的影响

The Effect of Different Mannobiose on the Aggregation of Saccharomyces Cerevisiae by Pathogenic Escherichia coli from Chicken

本研究首先通过D-甘露糖解聚试验确定所选取的大肠杆菌为含有Ⅰ型菌毛的甘露糖敏感型菌株,并利用显微镜观察初步比较α-甘露二糖和β-甘露二糖解除大肠杆菌凝聚酵母细胞活性的差异。随后采用分光光度计浊度计算法测定大肠杆菌和酵母细胞的最佳凝聚条件以及α-甘露二糖和β-甘露二糖的解聚活性。结果显示:所选取的鸡源致病性大肠杆菌为甘露糖敏感型菌株,其对酵母细胞的粘附能力能够被D-甘露糖所抑制;α-甘露二糖、β-甘露二糖对大肠杆菌凝聚酵母细胞均具有解聚活性。其中α-甘露二糖能更有效地解除鸡源致病性大肠杆菌对酵母细胞凝聚作用。

The results observed by optical microscope showed that the E. coli strain, what we used in the study, was a D-mannose sensitive strain, and it also found that those two different mannobiose had distinct inhibition effects. The optimum aggregate condition between E. coli and S. cerevisiae was determined by a modified spectrophotometer method, and through this method, the abilities of D-mannose, α-mannobiose and β-mannobiose to disaggregate E. coli and S. cerevisiae were also measured, respectively. D-mannose had the highest activity to disaggregation, since the pathogenic E. coli was the D-mannose sensitive strain. It suggested that α-mannobiose binding to E. coli＇s fimbriae was much stronger than β-mannobiose, so which had more efficiency to E. coli and S. cerevisiae disaggregation.