FIG 1.

Spore resistance to irradiation with X rays (A), protons (B), and high-energy charged Fe ions (C). Spores differing in various core components, including major α/β-type SASP, the single γ-type SASP, and Ca-DPA (due to loss of DPA synthetase encoded by spoVF), or core water content (due to the dacB mutation), with (white bars) and without (gray bars) protection by α/β-type SASP. Spores were irradiated in water, and D₁₀ values are expressed as averages ± standard deviations (n = 3) as described in the text. Lowercase letters above the bars denote groups significantly different by ANOVA (P < 0.05). Note the differences in the y axes of panels A, B, and C.