Related Experiment Video
Updated: Jun 26, 2026

Studying the Protein Quality Control System of D. discoideum Using Temperature-controlled Live Cell Imaging
Published on: December 2, 2016
Conservation and diversity of the IrrE/DdrO-controlled radiation response in radiation-resistant Deinococcus bacteria
Laurence Blanchard1,2,3, Philippe Guérin4, David Roche5,6
1Lab Bioenerget Cellulaire, CEA, DRF, BIAM, Saint-Paul-lez-Durance, France.
Abstract:
The extreme radiation resistance of Deinococcus bacteria requires the radiation-stimulated cleavage of protein DdrO by a specific metalloprotease called IrrE. DdrO is the repressor of a predicted radiation/desiccation response (RDR) regulon, composed of radiation-induced genes having a conserved DNA motif (RDRM) in their promoter regions. Here, we showed that addition of zinc ions to purified apo-IrrE, and short exposure of Deinococcus cells to zinc ions, resulted in cleavage of DdrO in vitro and in vivo, respectively. Binding of IrrE to RDRM-containing DNA or interaction of IrrE with DNA-bound DdrO was not observed. The data are in line with IrrE being a zinc peptidase, and indicate that increased zinc availability, caused by oxidative stress, triggers the in vivo cleavage of DdrO unbound to DNA. Transcriptomics and proteomics of Deinococcus deserti confirmed the IrrE-dependent regulation of predicted RDR regulon genes and also revealed additional members of this regulon. Comparative analysis showed that the RDR regulon is largely well conserved in Deinococcus species, but also showed diversity in the regulon composition. Notably, several RDR genes with an important role in radiation resistance in Deinococcus radiodurans, for example pprA, are not conserved in some other radiation-resistant Deinococcus species.
More Related Videos
12:08Rapid Antimicrobial Susceptibility Testing by Stimulated Raman Scattering Imaging of Deuterium Incorporation in a Single Bacterium
Published on: February 14, 2022
08:11Single-Animal, Single-Tube RNA Extraction for Comparison of Relative Transcript Levels via qRT-PCR in the Tardigrade Hypsibius exemplaris
Published on: January 3, 2025
Related Concept Videos
Defense Against Bacterial Pathogens
Phagocytes
Phagocytes are the frontline soldiers of the immune system. They include neutrophils and macrophages. Neutrophils are the most abundant type of white blood cell and are quickly mobilized to the site of infection. Macrophages are larger cells that patrol...
Endospores and Sporulation
Other Stress Responses in Bacteria
Other Unique Bacteria
Diversity of Archaea III
Diversity of Archaea IV