School of Immunity and Infection, University of Birmingham, Birmingham, UK.
FEMS Microbiol Lett. 2010 Oct;311(2):133-9. doi: 10.1111/j.1574-6968.2010.02081.x. Epub 2010 Aug 23.
The plasmid-encoded toxin, Pet, a prototypical member of the serine protease autotransporters of the Enterobacteriaceae, possesses an unusually long signal peptide, which can be divided into five regions termed N1 (charged), H1 (hydrophobic), N2, H2 and C (cleavage site) domains. The N1 and H1 regions correspond to a conserved N-terminal extension previously designated the extended signal peptide region (ESPR), while the N2, H2 and C regions resemble typical Sec-dependent signal sequences and exhibit considerable sequence variability. We have shown previously that the ESPR directs Sec-dependent, post-translational translocation of Pet across the bacterial inner membrane. In this study, we demonstrate that the ESPR is not essential for the secretion or the function of Pet.
质粒编码的毒素 Pet 是肠杆菌科丝氨酸蛋白酶自转运体的典型成员，具有非常长的信号肽，可分为五个区域，分别称为 N1（带电）、H1（疏水性）、N2、H2 和 C（切割位点）结构域。N1 和 H1 区域对应于先前指定的扩展信号肽区域 (ESPR) 的保守 N 端延伸，而 N2、H2 和 C 区域类似于典型的 Sec 依赖性信号序列，并表现出相当大的序列变异性。我们之前已经表明，ESPR 指导 Pet 在细菌内膜上进行 Sec 依赖性的翻译后转运。在这项研究中，我们证明了 ESPR 对于 Pet 的分泌或功能不是必需的。
