Radiation-response in <i>Deinococcus</i> bacteria: characterization of the transient IrrE-DdrO heterodimer complex.

ABSTRACT: Radiation resistance in Deinococcus requires an SOS-independent response mechanism, controlled by M78 family (COG2856) metallopeptidase IrrE and XRE family transcriptional repressor DdrO, to induce expression of DNA repair genes after exposure to radiation. DdrO must form dimers to bind target DNA sites. IrrE inactivates DdrO by cleaving the C-terminal dimerization domain of DdrO. However, the molecular basis of the interaction between IrrE and DdrO is still unknown. Here, we showed that IrrE is monomeric in solution and forms heterodimers with DdrO, with the N-terminal DNA-binding domain of DdrO contributing to the interaction. We further revealed that the initially isolated radiation-sensitive irrE mutant strain encodes an oxidation-sensitive IrrE protein affected in DdrO c

SUBMITTER: Reuzeau A 

PROVIDER: S-EPMC12828697 | biostudies-literature | 2026

REPOSITORIES: biostudies-literature