Wagner B, Wagner M
Zentralbl Bakteriol Orig A. 1975;231(1-3):81-91.
The carbohydrate of the cell wall of group C streptococci is one of the best known group-specific streptococcal antigens with respect to its chemical structure. In the present paper, the ultrastructural location of the carbohydrate was investigated by means of immunoelectronmicroscopic techniques. Besides group-specific antibodies, the specific binding of an agglutinin (protectin Anti-AHP) of the edible snail (Helix pomatia) to structures with terminal N-acetylgalactosamine was used to demonstrate the antigen. The agglutinin was extracted from the albumen gland of the snail and purified by column chromatography. By means of glutardialdehyde it was coupled with ferritin or horesradish peroxidase. The investigations were done on strains of Streptococcus equisimilis and Streptococcus equi. Str. pyogenes (group A streptococci) was used as a control. On whole cells of group C streptococci the carbohydrate was demonstrated on the surface of the triple-layered cell wall. Near the cross-wall the carbohydrate seems to be more concentrated. In the presence of N-acety-D-galactosamine the labelling of the cell wall was inhibited. N-acetyl-D-glucosamine did not have such an effect. On isolated cell walls, both the outer and the inner surface were tagged. This suggests that the group-specific carbohydrate covers the peptidoglycan (mucopeptide) on both sides. The cytoplasmic membrane shows no reaction.
就化学结构而言，C 组链球菌细胞壁的碳水化合物是最知名的组特异性链球菌抗原之一。在本文中，通过免疫电子显微镜技术研究了碳水化合物的超微结构定位。除了组特异性抗体外，还利用可食用蜗牛（玛瑙螺）的一种凝集素（保护素抗 AHP）与具有末端 N - 乙酰半乳糖胺的结构的特异性结合来证明该抗原。凝集素从蜗牛的蛋白腺中提取并通过柱色谱法纯化。通过戊二醛将其与铁蛋白或辣根过氧化物酶偶联。研究对象为类马链球菌和马链球菌菌株。化脓性链球菌（A 组链球菌）用作对照。在 C 组链球菌的全细胞上，碳水化合物在三层细胞壁的表面被证实。在横壁附近，碳水化合物似乎更集中。在 N - 乙酰 - D - 半乳糖胺存在的情况下，细胞壁的标记被抑制。N - 乙酰 - D - 葡萄糖胺没有这种作用。在分离的细胞壁上，外表面和内表面都有标记。这表明组特异性碳水化合物覆盖了两侧的肽聚糖（粘肽）。细胞质膜无反应。
