Generation of a mature streptococcal cysteine proteinase is dependent on cell wall-anchored M1 protein
Generation of a mature streptococcal cysteine proteinase is dependent on cell wall-anchored M1 protein
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DOI：
10.1046/j.1365-2958.2000.01942.x
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发表时间：
2000-06-01
影响因子：
3.6
通讯作者：
Olsén, A
中科院分区：
文献类型：
--
作者：
Collin, M;Olsén, A
在本研究中，我们已经产生了化脓性链球菌，MC25，它缺乏M蛋白在其表面上的突变株，我们证明，这种菌株是无法产生一个成熟的28 kDa的半胱氨酸蛋白酶。此外，我们还证明了S. M1血清型的化脓性细菌依赖于细胞壁锚定的M蛋白将分泌的酶原切割成成熟的半胱氨酸蛋白酶。我们还表明MC 25分泌一种40 kDa的酶原，其构象与野生型细菌分泌的不同。我们提供的数据表明切割位点没有被阻断，但据推测活性位点被阻断了。这表明，M蛋白，当锚定到细胞壁，是参与解折叠的酶原和生成的成熟的半胱氨酸蛋白酶，可以在还原条件下激活。我们的数据增加了新的方面之间的相互作用的两个重要的毒力因子的S。化脓性链球菌、链球菌半胱氨酸蛋白酶和M蛋白。
In the present study, we have generated a mutant strain of Streptococcus pyogenes, MC25, which lacks M protein on its surface, and we demonstrate that this strain is unable to generate a mature 28 kDa cysteine proteinase. Furthermore, we show that S. pyogenes bacteria of M1 serotype are dependent on cell wall-anchored M protein to cleave the secreted zymogen into a mature cysteine proteinase. We also show that MC25 secretes a 40 kDa zymogen, having a conformation different from that secreted by wild-type bacteria. We provide data showing that the cleavage site is not blocked but, presumably, the active site is. This suggests that M protein, when anchored to the cell wall, is involved in the unfolding of the zymogen and generation of a mature cysteine proteinase that can be activated under reducing conditions. Our data add new aspects to the interaction between two important virulence factors of S. pyogenes, the streptococcal cysteine proteinase and M protein.