CLUFF L E
J Exp Med. 1954 Oct 1;100(4):391-404. doi: 10.1084/jem.100.4.391.
The endotoxins of the Gram-negative bacteria have similar biological and chemical properties. The toxic antigen of Shigella flexneri Type Z was selected as a representative endotoxin, and it was confirmed that the antigen consists of a polysaccharide conjugated with phospholipid and protein. By the technique of zone electrophoresis, the polysaccharide of the purified endotoxin was shown to be conjugated with each of three different proteins, and each conjugate proved toxic and antigenic for the rabbit. Two of the protein conjugates were digested by trypsin and the released polysaccharide appeared to conjugate with the remaining trypsin-resistant protein. Immunological analysis revealed that the purified toxic antigen is heterogeneous and that the polysaccharide and protein components possessed serological activity. The trypsin-treated toxin had a single electrophoretic zone and its precipitation in gel suggested immunological purity. Proteolytic treatment of the endotoxin did not destroy its toxicity or antigenicity for the rabbit.
革兰氏阴性菌的内毒素具有相似的生物学和化学特性。福氏志贺菌Z型的毒性抗原被选为代表性内毒素，已证实该抗原由与磷脂和蛋白质结合的多糖组成。通过区带电泳技术，纯化内毒素的多糖显示与三种不同蛋白质中的每一种结合，并且每种结合物对兔子都具有毒性和抗原性。其中两种蛋白质结合物被胰蛋白酶消化，释放出的多糖似乎与剩余的抗胰蛋白酶蛋白质结合。免疫分析表明，纯化的毒性抗原是异质的，多糖和蛋白质成分具有血清学活性。经胰蛋白酶处理的毒素有一个单一的电泳区，其在凝胶中的沉淀表明具有免疫纯度。内毒素的蛋白水解处理并未破坏其对兔子的毒性或抗原性。
