Role of Mn²⁺ and Compatible Solutes in the Radiation Resistance of Thermophilic Bacteria and Archaea

Figure 1

Protection of enzyme activity. The restriction enzyme DdeI was irradiated up to 12 kGy in enzyme-free cell extracts (UFs) of H. salinarum, R. radiotolerans, and R. xylanophilus (diluted to 0.2x). Residual restriction enzyme activity was assayed by the digestion of pUC19 plasmid DNA; fragments were analyzed by agarose gel electrophoresis. The first lanes are molecular size ladders.

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