Department of Bacteriology, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Nagoya, Japan.
APMIS. 2010 Mar;118(3):167-78. doi: 10.1111/j.1600-0463.2009.02574.x.
Streptococcal toxic shock syndrome (STSS) is a re-emerging infectious disease in Japan and many other developed countries. Epidemiological studies have revealed that the M1 serotype of Streptococcus pyogenes is the most dominant causative isolate of STSS. Recent characterization of M1 isolates revealed that the mutation of covS, one of the two-component regulatory systems, plays an important role in STSS by altering protein expression. We analyzed the M1 S. pyogenes clinical isolates before or after 1990 in Japan, using two-dimensional gel electrophoresis (2-DE) and pulsed-field gel electrophoresis (PFGE). PFGE profiles were different between the isolates before and after 1990. Markedly different profiles among isolates after 1990 from STSS and pharyngitis patients were detected. Sequence analysis of two-component regulatory systems showed that covS mutations were detected not only in STSS but also in three pharyngitis isolates, in which proteins from the culture supernatant displayed the invasive type. The mutated CovS detected in the pharyngitis isolates had impaired function on the production of streptococcal pyrogenic exotoxin B (SpeB) analyzed by 2-DE. These results suggest that several covS mutations that lead to the malfunction of the CovS protein occurred even in pharyngeal infection.
链球菌中毒性休克综合征（STSS）是日本和许多其他发达国家重新出现的传染病。流行病学研究表明，化脓性链球菌的 M1 血清型是 STSS 的最主要致病分离株。最近对 M1 分离株的特征分析表明，两个组件调节系统之一 covS 的突变通过改变蛋白质表达在 STSS 中起重要作用。我们使用二维凝胶电泳（2-DE）和脉冲场凝胶电泳（PFGE）分析了日本 1990 年前后的 M1 酿脓链球菌临床分离株。PFGE 图谱在 1990 年前和 1990 年后的分离株之间存在差异。在 1990 年后从 STSS 和咽炎患者中检测到与分离株之间明显不同的图谱。对双组分调节系统的序列分析表明，covS 突变不仅在 STSS 中检测到，而且在三个咽炎分离株中也检测到，其中培养上清液中的蛋白质显示侵袭型。在咽炎分离株中检测到的突变 CovS 通过 2-DE 分析显示，其对化脓性链球菌外毒素 B（SpeB）的产生功能受损。这些结果表明，即使在咽部感染中，也会发生导致 CovS 蛋白功能障碍的几种 covS 突变。
