Differential Radio-Tolerance of Nutrition-Induced Morphotypes of Deinococcus radiodurans R1
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Deinococcus radiodurans R1 is a highly radio-tolerant bacterium. Depending on the nutrient availability D. radiodurans R1 exists in three morphologies viz. monococcal, diplococcal and tetracoccal. In this study, we examined whether nutrition-induced morphotypes of D. radiodurans showed similar DNA damage upon gamma radiation exposure. Total DNA damage after radiation exposure was estimated by comparing percent double-strand breaks (DSBs) in genomic DNA. It was found that all three morphotypes exhibited different radiation tolerances which were also dependent on the radiation dose given. Monococcal forms were found to be most radio-tolerant at most of the tested radiation doses. Results showed that these nutrient-starved-condition induced morphotypes show lesser DNA DSBs upon irradiation, hence show higher radio-tolerance.
KeywordsConfocal Laser Scanning Microscope Stringent Response Repair Machinery Deinococcus Radiodurans DSBs Repair
The authors thank Dr. Puspalatha Rajesh, WSCD, BARC, Kalpakkam, for extending the support of irradiation facility.
Conflict of interest
The authors of the manuscript declare no conflict of interest.
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