Antioxidant defense of Deinococcus radiodurans: how does it contribute to extreme radiation resistance?

Abstract

Purpose

Deinococcus radiodurans is an extremely radioresistant bacterium characterized by D₁₀ of 10 kGy, and able to grow luxuriantly under chronic ionizing radiation of 60 Gy/h. The aim of this article is to review the antioxidant system of D. radiodurans and its possible role in the unusual resistance of this bacterium to ionizing radiation.

Conclusions

The unusual radiation resistance of D. radiodurans has apparently evolved as a side effect of the adaptation of this extremophile to other damaging environmental factors, especially desiccation. The antioxidant proteins and low-molecular antioxidants (especially low-molecular weight Mn²⁺ complexes and carotenoids, in particular, deinoxanthin), as well as protein and non-protein regulators, are important for the antioxidant defense of this species. Antioxidant protection of proteins from radiation inactivation enables the repair of DNA damage caused by ionizing radiation.

Keywords:

• Deinococcus radiodurans
• ionizing radiation
• antioxidant
• manganese
• deinoxanthin
• bacillithiol

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.

Notes on contributors

Izabela Sadowska-Bartosz

Prof. Dr. hab. Izabela Sadowska-Bartosz is the Head of the Laboratory of Analytical Biochemistry in the Institute of Food Technology and Nutrition, College of Natural Sciences, University of Rzeszów. She is a member of the Council of the Society for Free Radical Research-Europe.

Grzegorz Bartosz

Prof. Dr. hab. Grzegorz Bartosz is a senior scientist in the Institute of Food Technology and Nutrition, College of Natural Sciences, University of Rzeszów.