Recent progress in understanding the molecular mechanisms of radioresistance in Deinococcus bacteria

Abstract

The deleterious effects of ionizing radiation are a major concern of the modern world. In the last decades, outstanding interest has been given to developing new therapeutic tools designed for protection against the toxic effects of ionizing radiation. Deinococcus spp. are among the most radioresistant organisms on Earth, being able to survive extreme doses of radiation, 1000-fold higher than most vertebrates. The molecular mechanisms underlying DNA repair and biomolecular protection, which are responsible for the remarkable radioresistance of Deinococcus bacteria, have been a debatable subject for the last 60 years. This paper is focused on the most recent findings regarding the molecular background of radioresistance and on Deinococcus bacteria response to oxidative stress. Novel proteins and genes involved in the highly regulated DNA repair processes, and enzymatic and non- enzymatic antioxidant systems are presented. In addition, a recently proposed mechanism that may contribute to oxidative damage protection in Deinococcus bacteria is discussed. A better understanding of these molecular mechanisms may draw future perspectives for counteracting radiation-related toxicity.

Comparative Proteomics Analysis Reveals New Features of the Oxidative Stress Response in the Polyextremophilic Bacterium Deinococcus radiodurans

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Application of iChip to Grow “Uncultivable” Microorganisms and its Impact on Antibiotic Discovery

“…Humans have evolved from single cell ancestors and as a species, have grown amongst a world teeming with microorganisms. From scalding volcanic vents in deep oceans to radioactive surroundings, microorganisms not only occupy the outside world but also exist in our internal organs, such as the GI tract (7,8). Microbiota refers to "the ecological community of commensal, symbiotic, and pathogenic microorganisms that share our body space."…”

PprM, a Cold Shock Domain-Containing Protein from Deinococcus radiodurans, Confers Oxidative Stress Tolerance to Escherichia coli

“…Various enzymatic and non-enzymatic anti-oxidative systems, redundancy in DNA repair genes with a unique DNA repair machinery called extended synthesis dependent strand annealing (ESDSA), and some physical characteristics of nucleoids, which are advantageous to DNA repair, contribute to the extreme resistance of D. radiodurans (Ishino and Narumi, 2015; Munteanu et al, 2015). However, the precise mechanisms governing the multiple resistance characteristics of this organism remain unclear.…”