Bestimmung von Einzel- und Doppelbrüchen in bestrahlter desoxyribonukleinsäure durch die Molekulargewichtsverteilung

摘要: Abstract Determination of single and double breaks in irradiated DNA from the distribution molecular weight 1. was isolated calf thymus with phenol purified avoiding any precipitation. The 0.01 M NaCl (200 μg/ml) X-rays sedimented analytical ultracentrifuge native denatured states. sedimentation coefficients determined by an analysis boundaries. calculation checked separated fractions different size. 2. distributions were transformed into weight. relationship between mol. wt. s can be a comparative measurement viscocity. 3. permits molecule. number increases linearly dose, whereas square dose. It demonstrated that break occurs whenever two are opposite positions or at distance not more than 3 nucleotide pairs. 4. samples reveals larger molecules would expected random breaks. This observation could explained irradiation-induced polymerisation occurring besides