Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, Suwon 440-746, Korea.
Protein Sci. 2010 Jun;19(6):1258-63. doi: 10.1002/pro.393.
The sigmaE-dependent stress response in bacterial cells is initiated by the DegS- and RseP-regulated intramembrane proteolysis of a membrane-spanning antisigma factor, RseA. RseB binds to RseA and inhibits its sequential cleavage, thereby functioning as a negative modulator of this response. In the crystal structure of the periplasmic domain of RseA bound to RseB, the DegS cleavage site of RseA is unstructured, however, its P1 residue is buried in the hydrophobic pocket of RseB, which suggests that RseB binding blocks the access of DegS to the cleavage site.
细菌细胞中依赖于 sigmaE 的应激反应是由 DegS 和 RseP 调节的跨膜抗 sigma 因子 RseA 的内肽酶切割所引发的。RseB 与 RseA 结合并抑制其顺序切割,从而作为该反应的负调节剂发挥作用。在与 RseB 结合的 RseA 周质结构域的晶体结构中,RseA 的 DegS 切割位点没有结构,但它的 P1 残基被埋在 RseB 的疏水口袋中,这表明 RseB 结合阻止了 DegS 进入切割位点。