乳酸菌和大肠杆菌对固定化犬肠道黏蛋白模型的黏附性

Microbial host interactions in vitro adhesion to mucus isolated from canine different intestinal compartments and inhibition of pathogens by selected lactobacilli

采用固定黏蛋白模型,结合细菌同位素γ-32P-ATP标记法,探讨犬源肠球菌E01和E16、犬源大肠杆菌DE、鸡源德氏乳酸杆菌德氏亚种N11及猪源约氏乳杆菌JJB3和致病性大肠杆菌ATCC25922和CVCC2060对本地犬各肠段黏蛋白的黏附能力;肠球菌E16和大肠杆菌DE各自的黏附机制;2株犬源肠球菌以3种作用方式(排斥、竞争、取代)对2株致病性大肠杆菌的黏附抑制作用。结果表明,各测试菌株在犬各肠段黏蛋白模型上的黏附值均不同;2株犬源肠球菌和1株猪源乳酸菌的黏附性能显著优于犬源大肠杆菌DE和2株致病性大肠杆菌;乳酸肠球菌E16表面的碳水化合物结构和糖蛋白参与了黏附过程,大肠杆菌菌体蛋白在黏附过程中发挥一定作用;乳酸肠球菌的黏附受体对高碘酸钠和胰蛋白酶处理不敏感,大肠杆菌DE的黏附受体具有碳水化合物结构,可能为糖蛋白类物质;在肠球菌与病源菌的3种作用方式中,取代和排斥方式对病原菌黏附抑制效果较好。这表明2株犬源肠球菌具开发为益生菌的潜力。

The present study described the adhesion of four LAB strains（E.faecium E01 and E.faecium E16 originated from canine,L.johnsonii JJB3 originated from swine,L.delbrueckii subsp.Delbrueckii N11 originated from chicken） and two zoonotic pathogens（Escherichia coli ATCC25922 and Escherichia coli CVCC2060） to immobilized mucus isolated from canine different intestinal compartments in vitro.All tested strains were found to have different adhesion values in different gut compartments.The adhesion values of E.faecium E01,E.faecium E16 and L.johnsonii JJB3 were significantly higher（P〈0.05） than the other two zoonotic pathogens.At the same time,we evaluated the ability of two canine originated LAB strains（E.faecium E01 and E.faecium E16） to inhibit,displace and compete with two zoonotic pathogens（E.coli ATCC25922 and E.coli CVCC2060） in order to test the influence of the presence of the other probiotic in the adhesion pathogens to immobilized mucus isolated from canine jejunum in vitro.The results showed that two canine originated LAB strains could significantly reduce the adhesion of two zoonotic pathogens in inhibition and displacement way（P〈0.05）.E.faecium E01 and E.faecium E16 have high adhesion ability and may be regarded as potential probiotics.