Radiation resistance and genome structure of <i>D. geothermalis</i> and <i>D. radiodurans</i>. A, IR (<sup>60</sup>Co, 5.5 kGy/h).

<p>B, UV (254 nm) (3 J/m<sup>2</sup> s<sup>−1</sup>). Open circle, <i>D. radiodurans</i> (32°C); open triangle, <i>D. geothermalis</i> (50°C); and open square, <i>D. geothermalis</i> (32°C). Values are from three independent trials with standard deviations shown. At near-optimal growth temperatures, the 10% survival values (D<sub>10</sub>) following IR for <i>D. radiodurans</i> (32°C) and <i>D. geothermalis</i> (50°C) are 15 kGy; for <i>E. coli</i>, 0.7 kGy (37°C) <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0000955#pone.0000955-Daly1" target="_blank">[5]</a>; and for <i>T. thermophilus</i> (HB27) 0.8 kGy (65°C) <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0000955#pone.0000955-Omelchenko1" target="_blank">[27]</a>. C, PFGE of genomic DNA prepared from irradiated (0.2 kGy) <i>D. radiodurans</i> (DR+IR) and <i>D. geothermalis</i> (DG+IR); and genomic DNA from non-irradiated <i>D. geothermalis</i> digested with <i>Spe</i>I (DG+<i>Spe</i>I). (M) PFGE DNA size markers. PFGE was as described previously <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0000955#pone.0000955-Daly7" target="_blank">[77]</a>.</p>