A Pair of Circularly Permutated PDZ Domains Control RseP, the S2P Family Intramembrane Protease of Escherichia coli
A Pair of Circularly Permutated PDZ Domains Control RseP, the S2P Family Intramembrane Protease of Escherichia coli
复制标题
DOI：
10.1074/jbc.m806603200
复制
发表时间：
2008-12-12
影响因子：
4.8
通讯作者：
Akiyama, Yoshinori
中科院分区：
文献类型：
--
作者：
Inaba, Kenji;Suzuki, Mamoru;Akiyama, Yoshinori
The sigma(E) pathway of extracytoplasmic stress responses in Escherichia coli is activated through sequential cleavages of the anti-sigma(E) protein, RseA, by membrane proteases DegS and RseP. Without the first cleavage by DegS, RseP is unable to cleave full-length RseA. We previously showed that a PDZ-like domain in the RseP periplasmic region is essential for this negative regulation of RseP. We now isolated additional deregulated RseP mutants. Many of the mutations affected a periplasmic region that is N-terminal to the previously defined PDZ domain. We expressed these regions and determined their crystal structures. Consistent with a recent prediction, our results indicate that RseP has tandem, circularly permutated PDZ domains (PDZ-N and PDZ-C). Strikingly, almost all the strong mutations have been mapped around the ligand binding cleft region in PDZ-N. These results together with those of an in vitro reaction reproducing the two-step RseA cleavage suggest that the proteolytic function of RseP is controlled by ligand binding to PDZ-N.
