Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium.
Infect Immun. 2019 Jun 20;87(7). doi: 10.1128/IAI.00889-18. Print 2019 Jul.
Infection with results in mucoid hemorrhagic diarrhea. This pathogen is associated with the colonic mucus layer, mainly composed of mucins. Infection regulates mucin -glycosylation in the colon and increases mucin secretion as well as binding sites on mucins. Here, we analyzed potential mucin epitopes for adhesion in the colon, as well as the effect of colonic mucins on bacterial growth. Associations between binding to pig colonic mucins and mucin glycan data showed that binding was associated with the presence of -glycolylneuraminic acid (NeuGc) on mucins. The role of sialic acid in adhesion was analyzed after the removal of sialic acid residues on the mucins by enzymatic treatment with sialidase A, which decreased bacterial binding to the mucins. The effect of pig colonic mucins on growth was determined in carbohydrate-free medium. growth increased in the presence of mucins from two out of five infected pigs, suggesting utilization of mucins as a carbon source for growth. Additionally, bacterial growth was enhanced by free sialic acid and -acetylglucosamine. The results highlight a role of sialic acid as an adhesion epitope for interaction with colonic mucins. Furthermore, the mucin response and glycosylation changes exerted in the colon during infection result in a potentially favorable environment for pathogen growth in the intestinal mucus layer.
感染导致粘液血性腹泻。这种病原体与结肠粘液层有关，主要由粘蛋白组成。感染调节结肠粘蛋白糖基化，增加粘蛋白分泌和粘蛋白上的结合位点。在这里，我们分析了结肠中潜在的粘蛋白表位用于粘附，以及结肠粘蛋白对细菌生长的影响。与猪结肠粘蛋白结合的分析表明，结合与粘蛋白上存在β-甘油酰基神经氨酸（NeuGc）有关。通过用神经氨酸酶 A 进行酶处理去除粘蛋白上的唾液酸残基后，分析了唾液酸在粘附中的作用，这降低了细菌与粘蛋白的结合。在无碳水化合物培养基中确定了猪结肠粘蛋白对生长的影响。来自五头感染猪中的两头的粘蛋白的存在增加了生长，表明粘蛋白被用作生长的碳源。此外，游离唾液酸和 N-乙酰葡萄糖胺增强了细菌的生长。结果强调了唾液酸作为与结肠粘蛋白相互作用的粘附表位的作用。此外，在感染期间结肠中产生的粘蛋白反应和糖基化变化导致肠道粘液层中病原体生长的潜在有利环境。
