Mantle M, Husar S D
Department of Medical Biochemistry, University of Calgary, Alberta, Canada.
Infect Immun. 1994 Apr;62(4):1219-27. doi: 10.1128/iai.62.4.1219-1227.1994.
Plasmid-bearing (but not plasmid-cured) Yersinia enterocolitica is known to bind to purified small intestinal mucins from rabbits and humans. This study examined which region(s) of the mucin molecule is important for bacterial adherence. Pronase digestion of mucin and removal of nonglycosylated or poorly glycosylated peptide regions had no effect on bacterial binding, suggesting that plasmid-bearing Y. enterocolitica interacts with mucin carbohydrate. Periodate oxidation also did not alter bacterial adherence, indicating that vicinal hydroxyl groups in the mucin sugars are not important for binding. Boiling of mucin, depolymerization by reduction of disulfide bonds, or removal of noncovalently associated lipid actually enhanced bacterial adherence, suggesting that plasmid-bearing Y. enterocolitica can interact with additional domains in the mucin molecule revealed by these treatments. These domains were destroyed by pronase digestion. In delipidated mucin (but not in reduced or boiled mucin), binding to these domains appeared to be hydrophobic since it could be prevented by treatment of bacteria with tetramethyl urea. Oligosaccharides obtained from both human and rabbit small intestinal mucins were capable of inhibiting attachment of plasmid-bearing (but not plasmid-cured) Y. enterocolitica to mucin. After removal of terminal and backbone sugar residues by treatment of mucin with trifluoromethanesulfonic acid, binding of plasmid-bearing bacteria increased significantly when N-acetylgalactosamine, either alone or with galactose attached, was revealed, indicating that core regions of the sugar side chains are involved in bacterial binding. Adherence of plasmid-cured organisms was unaffected by trifluoromethanesulfonic acid treatment of mucin. We concluded that virulent Y. enterocolitica interacts with the carbohydrate moiety of native small intestinal mucin through a plasmid-mediated process. When mucin becomes denatured, binding of the organism can increase through hydrophobic and nonhydrophobic interactions with (most likely) the mucin protein.
已知携带质粒（但未消除质粒）的小肠结肠炎耶尔森菌能与从兔子和人类中纯化得到的小肠粘蛋白结合。本研究检测了粘蛋白分子的哪些区域对细菌黏附至关重要。用链霉蛋白酶消化粘蛋白并去除非糖基化或糖基化程度低的肽区域对细菌结合没有影响，这表明携带质粒的小肠结肠炎耶尔森菌与粘蛋白碳水化合物相互作用。高碘酸盐氧化也未改变细菌黏附，表明粘蛋白糖中的邻位羟基对结合并不重要。煮沸粘蛋白、通过还原二硫键使其解聚或去除非共价结合的脂质实际上增强了细菌黏附，这表明携带质粒的小肠结肠炎耶尔森菌可以与这些处理所揭示的粘蛋白分子中的其他结构域相互作用。这些结构域被链霉蛋白酶消化破坏。在脱脂粘蛋白中（但在还原或煮沸的粘蛋白中未观察到），与这些结构域的结合似乎是疏水的，因为用四甲基脲处理细菌可以阻止这种结合。从人类和兔子小肠粘蛋白中获得的寡糖能够抑制携带质粒（但未消除质粒）的小肠结肠炎耶尔森菌与粘蛋白的附着。用三氟甲磺酸处理粘蛋白去除末端和主链糖残基后，当单独的N - 乙酰半乳糖胺或连接有半乳糖的N - 乙酰半乳糖胺暴露时，携带质粒的细菌的结合显著增加，表明糖侧链的核心区域参与细菌结合。消除质粒的菌株的黏附不受三氟甲磺酸处理粘蛋白的影响。我们得出结论，有毒力的小肠结肠炎耶尔森菌通过质粒介导的过程与天然小肠粘蛋白的碳水化合物部分相互作用。当粘蛋白变性时，该菌的结合可通过与（很可能）粘蛋白蛋白质的疏水和非疏水相互作用而增加。
