Hill H Z, Schiff J A, Epstein H T
Biophys J. 1966 Mar;6(2):125-33. doi: 10.1016/s0006-3495(66)86644-4.
Ultraviolet (UV) inactivation of green colony-forming ability of several different types of Euglena gracilis var. bacillaris was studied. The observed target numbers are not widely different, while the doses required to produce a single inactivation event (D(o)) vary with the type of cell used. In dark-grown cells adapting to the light in resting medium and in an X-ray-induced mutant, D(o) is proportional to the chlorophyll content of the cells. However, in hyperdeveloped cells which contain abnormally high amounts of chlorophyll, the correlation does not hold, suggesting that it is not chlorophyll per se which is responsible for the differences observed. D(o)'s of colony-forming ability (viability) of light-grown and dark-grown cells are found to differ by the same factor as those of green colony-forming ability. Stationary phase and exponential phase cells show a small difference in D(o) with no obvious difference in target multiplicity. The multiplicity of the various target curves has been re-evaluated by computer and found to be between 30 and 40.
研究了紫外线（UV）对几种不同类型纤细裸藻杆菌变种绿色菌落形成能力的灭活作用。观察到的靶标数量差异不大，而产生单个灭活事件所需的剂量（D₀）随所用细胞类型而变化。在黑暗生长的细胞中，于静止培养基中适应光照以及在X射线诱导的突变体中，D₀与细胞的叶绿素含量成正比。然而，在含有异常高含量叶绿素的过度发育细胞中，这种相关性并不成立，这表明造成观察到的差异的并非叶绿素本身。发现光照生长和黑暗生长细胞的菌落形成能力（活力）的D₀差异与绿色菌落形成能力的D₀差异相同。稳定期和指数期细胞的D₀显示出微小差异，靶标多样性无明显差异。通过计算机重新评估了各种靶标曲线的多样性，发现其在30至40之间。
