The inactivation of adenoviruses by ultraviolet irradiation and nitrous acid

The Physical State of Viral Nucleic Acid and the Sensitivity of Viruses to Ultraviolet Light

Ultraviolet light action spectra in the range 2250 to 3020 A have been determined for the plaque-forming ability of the following bacteriophage and animal viruses: T-2, varphix-174, R-17, fr, MS2, 7-S, fd, vesicular stomatitis, vaccinia, encephalomyocarditis, reovirus-3, and polyoma. Absolute quantum yields for the plaque-forming ability of MS2, fr, fd, varphix-174, and T-2 were determined over the range 2250 to 3020 A. Relative quantum yields for plaque-forming ability indicated that viruses with single-stranded nucleic acid were on the average ten times more sensitive to UV than double-stranded viruses. In addition for ten of the twelve viruses a relation existed between the shape of their action spectra and the stranded state of their nucleic acid. The ratio of the inactivation cross-section at 2650 A to that at 2250 A for these viruses was 1.0 for single-stranded viruses and 2.0 for viruses with double-stranded nucleic acid. The above relations were dependent on the stranded state of the nucleic acid not the ribose or deoxyribose form of the sugar present.

Inactivation of feline calicivirus and adenovirus type 40 by UV radiation

Little information regarding the effectiveness of UV radiation on the inactivation of caliciviruses and enteric adenoviruses is available. Analysis of human calicivirus resistance to disinfectants is hampered by the lack of animal or cell culture methods that can determine the viruses' infectivity. The inactivation kinetics of enteric adenovirus type 40 (AD40), coliphage MS-2, and feline calicivirus (FCV), closely related to the human caliciviruses based on nucleic acid organization and capsid architecture, were determined after exposure to low-pressure UV radiation in buffered demand-free (BDF) water at room temperature. In addition, UV disinfection experiments were also carried out in treated groundwater with FCV and AD40. AD40 was more resistant than either FCV or coliphage MS-2 in both BDF water and groundwater. The doses of UV required to achieve 99% inactivation of AD40, coliphage MS-2, and FCV in BDF water were 109, 55, and 16 mJ/cm(2), respectively. The doses of UV required to achieve 99% inactivation of AD40, coliphage MS-2, and FCV in groundwater were slightly lower than those in BDF water. FCV was inactivated by 99% by 13 mJ/cm(2) in treated groundwater. A dose of 103 mJ/cm(2) was required for 99% inactivation of AD40 in treated groundwater. The results of this study indicate that if FCV is an adequate surrogate for human caliciviruses, then their inactivation by UV radiation is similar to those of other single-stranded RNA enteric viruses, such as poliovirus. In addition, AD40 appears to be more resistant to UV disinfection than previously reported.

Inactivation of a turkey herpesvirus by ultra-violet light

The sensitivity to inactivation by ultraviolet light of the PB 1 strain of herpesvirus of turkeys (HVT) was determined and compared with the relative sensitivity of pseudo-rabies virus (PRV), another member of the herpesvirus group. HVT (PB1) was 6.3 times more resistant than PRV when assayed in chick embryo fibroblasts. The survival curve of HVT (strain PB1) had one component and the survival curve of PRV had two components. Survival curves of HVT and PRV in chick embryo fibroblasts treated with caffeine and in duck embryo fibroblasts are also presented. Evidence was obtained for host cell reactivation of HVT and PRV in chick embryo fibroblasts. Multiplicity reactivation could be clearly demonstrated for UV-irradiated PRV, but not for HVT.

Analysis of minimal functions of simian virus 40. II. Enhancement of oncogenic transformation in vitro by UV irradiation

After light UV irradiation (5,000 to 10,000 ergs/mm(2)) "complete" and "defective" simian virus 40 (SV40) showed an enhancement of oncogenic transformation capacity in Syrian hamster kidney cells in vitro up to 180 and 270% of the controls, respectively. Simultaneously with the enhancement of transformation, an increase in T-antigen induction was observed in CV-1 cells infected with light UV-irradiated SV40; infectivity, however, was correspondingly reduced by 1 log(10). After strong UV irradiation (10,000 to 80,000 ergs/mm(2)) of "complete" and "defective" SV40, transformation capacity in vitro proved to be the most resistant viral function. It was only slightly reduced in comparison with a 4 to 5 log(10) reduction of infectivity. T-antigen induction of SV40 was also equally resistant to strong UV irradiation. We found no evidence of "multiplicity reactivation" involved in the high resistance of transformation capacity of SV40 after UV irradiation. Syrian hamster kidney cells transformed in vitro by UV-irradiated SV40 contained the SV40-specific T-antigen and showed the same morphology and growth characteristics as cells transformed by non-irradiated "complete" or "defective" SV40. They induced malignant tumors after subcutaneous inoculation into Syrian hamsters.

Role of ribonucleic acid biosynthesis in multiplication of type 5 adenovirus

Flanagan, John F. (University of Pennsylvania, Philadelphia), and Harold S. Ginsberg. Role of ribonucleic acid biosynthesis in multiplication of type 5 adenovirus. J. Bacteriol. 87:977-987. 1964.-The requirement for ribonucleic acid (RNA) biosynthesis in the multiplication of type 5 adenovirus was investigated by using radioactive phosphorus to label nucleic acids and two pyrimidine analogues, 6-azauridine and 5-fluorouracil or 5-fluorouridine, to inhibit synthesis of functional RNA. The data indicate that biosynthesis of RNA after infection is essential for production of virus-specific deoxyribonucleic acid, virus antigens, and infectious particles. The onset of essential RNA synthesis occurs 8 to 9 hr after virus infection and prior to the biosynthesis of other known virus-induced macromolecules.