الفهرس 
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Abstract
The aim of present work is to study the effect of ultraviolet irradiation on the activity of the Vesicular Stomatitis Virus (VSV) as hepatitis C virus (HCV) model, evaluating the inactivation parameters for the viral genes and calculation of the energy amount which required to complete destruction of the viral RNA and proteins.
By cell culture techniques, the Vesicular Stomatitism Virus was loaded on gamma globulin, and stock virus titer was detected. Samples of the Vesicular Stomatitis Virus and gamma globulin mix were exposed to ultraviolet- irradiation for different times up to 24 hours, and virus titer was detected for each sample. Ultraviolet source of wavelength = 253.7 nm, intensity: 2.84 W/cm2 was used in this work.
Using the spectrophotometry and electrophoresis techniques the normal sample and irradiated samples showed maximum absorbance with different values at wavelength = 230 and 260 nm. Analysis at wavelength = 260 nm ( the maximum absorbance of nucleic acid) proved that, after 24 hours of ultraviolet- irradiation, RNA of the Vesicular Stomatitis Virus denaturated and its activity is nearly stopped.
Samples of gamma globulin without the virus were exposed to ultraviolet – irradiation for 1,2,8,16,24 hours and it was found that, after all previous times of irradiation there was some changes in gamma globulin structure. Increasing time of exposure of the Vesicular Stomatitis Virus particles to ultraviolet radiation caused differential inhibition of the synthesis in vitro of the viral particles in relating to time.
From the obtained results from the gel electrophoresis technique it was noted that VSV and gamma globulin mix samples showed smear due to the protein overlapping while gamma globulin alone showed different integrated bands. It was not helpful in analysis for the samples of the Vesicular Stomatitis Virus and gamma globulin mix, but it was helpful with gamma globulin samples.
The inactivation parameters of the viral RNA were found to be dependent on time of irradiation and the synthesis of RNA strand showed single hit kinetics after each time of irradiation. Changes in the inactivation parameter were evaluated for each gene of the five proteins in the viral RNA; the results suggest that, the ultraviolet inactivation process is mainly dependent on the molecular weight of the virus and time of exposure.
Calculation of the lethal hit per incident hit proved that, as the time of irradiation increases, the value of the hit to be lethal increases. Energy values for complete destruction of peptide bonds of the five viral proteins and phosphodiester bonds of the viral RNA were calculated and percentage of broken peptide bonds of each protein was determined, and it was found that, peptide bonds of N, G, and (M, P) proteins were completely destructed after 4, 8 and 16 hours respectively .