Study of the relationship between bacteriophage and selective host cells according to different conditions of UV-C irradiation

We investigate the potential for reactivation to restore infectivity to UV-damaged bacteriophage 2MPØ isolated from wastewater. The virus belongs to the Myoviridae family of the tailed phages. This Phage was chosen for detailed analysis, and was inspected by electron microscopy, host range determination. In addition, we explore the dynamics of bacteriophage host interactions in different conditions of UV-C irradiation. The inactivation kinetic or dose-response relationship was described by the method of plaque-forming ability. The UV-inactivation kinetic was represented in the exponential curve according to the model of Chick–Watson and Series-event kinetic model. In a 99.99% inactivation of 2MPØ bacteriophage which corresponded to 720 mW s/cm2 of UV-dose, high correlation was observed between the loss of infectivity and the increase of UV-C dose. The restore of infectivity of UVexposed bacteriophage was also determined under conditions which either activated or repressed the light-dependent photolyase enzyme in host cells, in order to examine the damage-dependent response of this bacterial repair system. The results of reactivation indicated that light-dependent repair (photoreactivation) was much more efficient than dark repair in restoring infectivity to bacteriophage damaged by UV-C radiation.

Our results clearly demonstrate that photoreactivation mechanism’s host cells of P. aeruginosa is important and may be essential for maintaining high concentrations of infectious bacteriophage in different conditions of UV-C irradiation. Photoreactivation could be the mechanism allowing for the persistence of viruses in surface waters. The data presented here indicate that the loss of viral infectivity resulting from solar radiation may be largely offset by in first order host-mediated light-dependent repair and secondary by host-mediated light-independent repair of the damaged DNA. 6. Perspectives The use of the bacteriophages was developed as alternative anti-infection modalities has become one of the highest priorities of modern medicine and biotechnology. The phagotherapy