The scientific revolution that unraveled the astonishing DNA repair capacity of the Deinococcaceae : 40 years on

• Published in: Canadian journal of microbiology Vol. 69; no. 10; pp. 369 - 386
• Main Author: Daly, Michael J
• Format: Journal Article
• Language: English
• Published: Canada NRC Research Press 01.10.2023; Canadian Science Publishing NRC Research Press
• Subjects: Antioxidants; Biotechnology; Coupling; Deinococcus; Deoxyribonucleic acid; Desiccation; DNA; DNA damage; DNA repair; Double-strand break repair; Genetic aspects; Genomes; Gram-positive bacteria; Holliday junctions; Metabolism; Metabolites; Microbiological research; Oxidative stress; Polyploidy; Proteomes; Radiation; Radiation tolerance; Radiobiology; Survivability; Survival; United States; Holliday junction; Mn antioxidant; Deinococcus; electron paramagnetic resonance; radiation; DNA repair
• DOI: 10.1139/cjm-2023-0059
• ISSN: 0008-4166

The family exhibits exceptional radiation resistance and possesses all the necessary traits for surviving in radiation-exposed environments. Their survival strategy involves the coupling of metabolic and DNA repair functions, resulting in an extraordinarily efficient homologous repair of DNA double-strand breaks (DSBs) caused by radiation or desiccation. The keys to their survival lie in the hyperaccumulation of manganous (Mn )-metabolite antioxidants that protect their DNA repair proteins under extreme oxidative stress and the persistent structural linkage by Holliday junctions of their multiple genome copies per cell that facilitates DSB repair. This coupling of metabolic and DNA repair functions has made polyploid bacteria a useful tool in environmental biotechnology, radiobiology, aging, and planetary protection. The review highlights the groundbreaking contributions of the late Robert G.E. Murray to the field of research and the emergent paradigm-shifting discoveries that revolutionized our understanding of radiation survivability and oxidative stress defense, demonstrating that the proteome, rather than the genome, is the primary target responsible for survivability. These discoveries have led to the commercial development of irradiated vaccines using Mn-peptide antioxidants and have significant implications for various fields.