Blomberg L, Henriksson A, Conway P L
Department of General and Marine Microbiology, University of Göteborg, Sweden.
Appl Environ Microbiol. 1993 Jan;59(1):34-9. doi: 10.1128/aem.59.1.34-39.1993.
Enteropathogenic Escherichia coli K88 colonizing the piglet ileum adhere to the mucosa by K88 fimbrial appendages. A recent study in our laboratory has implicated indigenous lactobacilli in the suppression of the colonization potential of enteropathogenic E. coli as measured by adhesion to ileal mucus. The aim of this study was to investigate the effect of Lactobacillus spp. of porcine origin on the adhesion of K88 fimbriae of E. coli. With an in vitro assay, the adhesion of E. coli K88ab strain G1108E and E. coli K88ac strain 1107 to 35-day-old piglet ileal mucus was studied in the presence of spent culture fluid of Lactobacillus spp. Detailed studies focused specifically on culture fluid of Lactobacillus fermentum 104R. Subsequently, the ileal mucus was exposed to the retentate of the spent culture fluid after dialysis and fractionation. Adhesion was confirmed to be attributable to K88 fimbriae when K88-specific monoclonal antibodies and isogenic mutants of E. coli K-12 with and without the plasmid containing the K88 gene were used. The active component was characterized by pretreatment of dialysis retentate with heat, periodate, pronase, and centrifugation, as well as by growth of the lactobacillus in various media and by assays at both 0 and 37 degrees C. All three lactobacilli of porcine origin reduced adhesion of E. coli K88 by approximately 50%. Inhibition occurred when mucus was pretreated with either spent culture dialysis retentate or the void volume (fraction of > 250,000 molecular weight) after gel filtration. The activity of the dialysis retentate was sensitive to pronase, but there was still activity at 0 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS)
定居于仔猪回肠的致病性大肠杆菌K88通过K88菌毛附属物黏附于黏膜。我们实验室最近的一项研究表明，通过对回肠黏液的黏附测定，本土乳酸菌可抑制致病性大肠杆菌的定植潜力。本研究的目的是调查猪源乳酸杆菌对大肠杆菌K88菌毛黏附的影响。通过体外试验，在乳酸杆菌属的陈旧培养液存在的情况下，研究了大肠杆菌K88ab菌株G1108E和大肠杆菌K88ac菌株1107对35日龄仔猪回肠黏液的黏附。详细研究特别聚焦于发酵乳杆菌104R的培养液。随后，将回肠黏液暴露于经过透析和分级分离的陈旧培养液的截留物中。当使用K88特异性单克隆抗体以及含有和不含有K88基因质粒的大肠杆菌K-12同基因突变体时，证实黏附归因于K88菌毛。通过用热、高碘酸盐、链霉蛋白酶处理透析截留物并进行离心，以及通过在各种培养基中培养乳酸菌并在0℃和37℃下进行测定来表征活性成分。所有三种猪源乳酸杆菌均使大肠杆菌K88的黏附减少了约50%。当黏液用陈旧培养液透析截留物或凝胶过滤后的空体积（分子量>250,000的级分）预处理时，会发生抑制作用。透析截留物的活性对链霉蛋白酶敏感，但在0℃时仍有活性。（摘要截短于250字）
