Gerlach D, Knöll H, Köhler W, Ozegowski J H, Hríbalova V
Zentralbl Bakteriol Mikrobiol Hyg A Med Mikrobiol Infekt Parasitol. 1983 Sep;255(2-3):221-33.
Production of erythrogenic toxin type B by Streptococcus pyogenes strain T19 was found to be strongly dependent on the pH of the cultivation medium. Maximum yields (greater than 100 mg of toxin/1) were obtained at pH 6.0. In contrast no toxin production was serologically detectable at pH values above 6.5. Purified B-toxin was shown to consist of two components when assayed by SDS-electrophoresis. The molecular weight of the two components was estimated to be 30 000 and 12 000. Isoelectric focusing revealed a heterogeneity of the preparation with isoelectric points between 8.0 and 9.0. Streptococcal proteinase precursor was isolated from culture supernatants of strains T19 and B220 by ammonium sulfate crystallization and purification on CM-Sepharose CL 6B. The protein obtained was homogeneous by SDS-gel electrophoresis and had a molecular weight of 44 000. After autocatalytic activation with mercaptoethanol two bands appeared corresponding to molecular weights 30 000 and 12 000. Isoelectric focusing of proteinase precursor preparations yielded a double band at pI 8.2-8.3. However, activation of precursor to active proteinase finally resulted in a change of the pI to 9.0. Erythrogenic toxin type B, streptococcal proteinase precursor, its intermediate activation products and the active proteinase itself reacted serologically identical with anti B-toxin antiserum. Streptococcal proteinase precursor provoked a delayed skin reaction and was pyrogenic as well as mitogenic. Its pyrogenic activity could be inhibited by antiserum against scarlet fever toxin (Wellcome Laboratories). We therefore believe erythrogenic toxin type B to be identical with streptococcal proteinase precursor. This helps to understand the heterogeneity of B toxin, its inactivation by trypsin and the different protocols for toxin production described in the literature.
已发现化脓性链球菌T19菌株产生B型产红细胞毒素强烈依赖于培养基的pH值。在pH 6.0时可获得最大产量（超过100毫克毒素/升）。相比之下，在pH值高于6.5时，血清学检测不到毒素产生。通过SDS电泳分析，纯化的B毒素显示由两个组分组成。这两个组分的分子量估计分别为30000和12000。等电聚焦显示该制剂具有异质性，等电点在8.0至9.0之间。通过硫酸铵结晶和在CM-Sepharose CL 6B上纯化，从T19和B220菌株的培养上清液中分离出链球菌蛋白酶前体。通过SDS凝胶电泳获得的蛋白质是均一的，分子量为44000。用巯基乙醇进行自催化激活后，出现了两条对应分子量为30000和12000的条带。蛋白酶前体制剂的等电聚焦在pI 8.2 - 8.3处产生一条双带。然而，前体激活为活性蛋白酶最终导致pI变为9.0。B型产红细胞毒素、链球菌蛋白酶前体、其中间激活产物和活性蛋白酶本身与抗B毒素抗血清的血清学反应相同。链球菌蛋白酶前体引起延迟性皮肤反应，具有致热和促有丝分裂作用。其致热活性可被抗猩红热毒素抗血清（威康实验室）抑制。因此，我们认为B型产红细胞毒素与链球菌蛋白酶前体相同。这有助于理解B毒素的异质性、其被胰蛋白酶灭活以及文献中描述的不同毒素生产方案。
