Efficacy and mechanisms of action of ionizing radiations on Pseudomonas aeruginosa bacterio phage F116 [electronic resource].

Includes references.

Influences of gamma rays and fast neutrons on efficacy and mechanisms of action on Pseudomonas aeruginosa bacteriophage F116 have been investigated. These mechanisms included, prophage induction, plaque forming ability, transducing particles and transduction efficiency. Survival percentages of 3 host strains, P AO1, MAM2 and PU17 have been seriously affected upon exposure to the ionizing radiation. Killing percentage ranged from 67.4 up to 78.9% when 5.6 xl08 n/cm2 of fast neutrons was used. Prophage F116 induction mechanism from the lysogenic strain PU17 (PU21 F 116) has also been influenced. At 3.0 KGy of gamma rays and 5.6 x 10 8 n/cm2 of neutrons resulting in 2-3 fold increase in prophage induction than control (zero- dose). Whereas, the induced phage was doubling (15.54) in fast neutrons than gamma irradiation (7.43). Subsequently, transduction frequency of streftomycin resistance gene using these induced phase reached 25.3x10-5 and 6.1x10-5 upon using fast neutrons and gamma rays, respectively. This was correlated with number of transuding particles when calculated at these doses. Moreover, transduction frequency was also enhanced by treating the recipient host cells with different doses. In addition, a dramatically loss in the activation of phage F116 was observed upon treating the phage particles. This inactivation was occurred in plaque forming units and transducing abilities. The results of this study showed that fast neutrons were more effective .on the previous phage F116 mechanisms than gamma rays. However, the effect was done depending on both.

Summary in Arabic.

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