FtsH-dependent processing of RNase colicins D and E3 means that only the cytotoxic domains are imported into the cytoplasm.

ABSTRACT: It has long been suggested that the import of nuclease colicins requires protein processing; however it had never been formally demonstrated. Here we show that two RNase colicins, E3 and D, which appropriate two different translocation machineries to cross the outer membrane (BtuB/Tol and FepA/TonB, respectively), undergo a processing step inside the cell that is essential to their killing action. We have detected the presence of the C-terminal catalytic domains of these colicins in the cytoplasm of target bacteria. The same processed forms were identified in both colicin-sensitive cells and in cells immune to colicin because of the expression of the cognate immunity protein. We demonstrate that the inner membrane protease FtsH is necessary for the processing of colicins D and E3 during th

SUBMITTER: Chauleau M 

PROVIDER: S-EPMC3190745 | biostudies-literature | 2011 Aug

REPOSITORIES: biostudies-literature