b) Pulse and chase experiment. Unsynchronized cells are incubated with 3HT for 1 hour and chased for another hour. Loss of radioactivity from DNA is indicated in percent. c) Unsynchronized cells are incubated with 3HT, and the incorporation rate into DNA per cell per hour is determined. d) Cells are incubated with 3HT for 19 hours. Nucleic acids are isolated, and the relative incorporation rate of radioactivity per nucleic acid content is determined. e) Resistance (R), Tolerance (T) or Sensitivity (S) after incubation with HU for three days monitoring cell count and cell survival by microscope. S means no surviving cell, T means decrease of cell number with at least 10% remaining cells, R means cell divisions occur (Results from two experiments). f) Cells are incubated for 19 hours with or without HU; nucleic acids are isolated and quantified. The quotient of the DNA content per sample without/with HU is indicated. 1 means the same amount with and without HU. 2 mean duplication of the DNA without HU and arrest of DNA replication with HU. Each number reflects the average of two samples per experiment, with two independent experiments unless indicated otherwise. n.d. not determined |
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| Table 2: Response of Cells. |
