Repair of CIP (10 μg/ml) induced DNA fragmentation. The distribution of the frequencies of the diffusion widths from the nucleoids were categorized according to the five classes of fragmentation level (0 to IV) presented in Table 1 and Fig. 2. The different repair times after exposure of TG1 E. coli to three doses of CIP (a: 10 μg/ml, b: 1 μg/ml, and c: 0.1 μg/ml) for 40 min are presented. Viability (%) is indicated next to each repair time. Each dose is shown with its respective culture (above) in which the antibiotic was present during the incubation time.