Yuyama Y, Yoshimatsu K, Ono E, Saito M, Naiki M
Faculty of Veterinary Medicine, Hokkaido University.
J Biochem. 1993 Apr;113(4):488-92. doi: 10.1093/oxfordjournals.jbchem.a124071.
Enterotoxigenic Escherichia coli possessing K99 fimbriae (E. coli K99) causes diarrhea in piglets of less than 1 week old. The first stage of the bacterial infection is adhesion by the fimbriae on the small intestinal mucosa and the adhesion is followed by colony formation. K99 fimbriae bind specifically to N-glycolylneuraminyl-lactosyl-ceramide, GM3(NeuGc) [Ono, E. et al. (1989) Infect. Immun. 57,907-911]. We examined the postnatal change of the content and the molecular species of GM3(NeuGc) in the small intestinal mucosa of 0- to 14-day-old piglets and adult pigs. GM3(NeuGc) was a major ganglioside of piglet intestinal mucosa. GM3(NeuGc) content was maximal at birth and gradually decreased to 1/16 in adult animals (5 months old). The ceramide moiety of piglet intestinal GM3(NeuGc) was characterized by the presence of 2-hydroxylated palmitic acid. 125I-labeled bacteria strongly bound to GM3(NeuGc) containing 2-hydroxylated palmitic acid and phytosphingosine compared with GM3(NeuGc) containing any other ceramide moiety. The time when this particular GM3(NeuGc) appears coincides with the time that the infection occurs, and it may explain the susceptibility of newborn piglets to E. coli K99 infection.
携带K99菌毛的产肠毒素大肠杆菌（大肠杆菌K99）可导致1周龄以内仔猪腹泻。细菌感染的第一阶段是菌毛黏附于小肠黏膜，随后形成菌落。K99菌毛特异性结合N - 羟乙酰神经氨酰乳糖基神经酰胺，即GM3（NeuGc）[小野，E.等人（1989年）。感染与免疫。57,907 - 911]。我们研究了0至14日龄仔猪和成年猪小肠黏膜中GM3（NeuGc）含量及分子种类的产后变化。GM3（NeuGc）是仔猪肠黏膜的主要神经节苷脂。GM3（NeuGc）含量在出生时最高，成年动物（5月龄）时逐渐降至1/16。仔猪肠道GM3（NeuGc）的神经酰胺部分特征在于存在2 - 羟基化棕榈酸。与含有任何其他神经酰胺部分的GM3（NeuGc）相比，125I标记的细菌与含有2 - 羟基化棕榈酸和植物鞘氨醇的GM3（NeuGc）强烈结合。这种特定GM3（NeuGc）出现的时间与感染发生的时间一致，这可能解释了新生仔猪对大肠杆菌K99感染的易感性。
