DSB repair kinetics during postirradiation recovery in D. radiodurans. D. radiodurans R1 (wild type) and Δdr1769 mutant (Δdr1769 mutant) cells were treated with 6.5 kGy gamma radiation and allowed to grow at different time periods (1.5, 4, 6, 24, and 48 h), and PFGE was carried out along with unirradiated (U) respective controls.