A Comparison of Ultraviolet Action Spectra for Vaccinia Virus and T2 Bacteriophage

The effect of monochromatic u.v. light on vaccinia virus was first studied by Rivers & Gates (1928) using irradiations at several wavelengths between 230 and 312 nm. Although their titration methods were understandably limited they found greatest activities at the wavelengths between 250 and 280 nm with a peak at 267 nm. A similar result was obtained by Rauth (1965), who included vaccinia virus in a comparison of action spectra of several animal and bacterial viruses. Numerous other reports of action spectra of viruses have been published, e.g. tobacco mosaic virus (Kleczkowski, 1963), bacteriophages T1 and T2 (Zelle & Hollaender, 1954) and influenza virus (Tamm & Fluke, 1950) and, in general, they too show peaks in the region of maximum nucleic acid absorption (260 to 265 nm).

However, a number of studies made with pox viruses irradiated with u.v. light from germicidal lamps have revealed a curious difference in the sensitivity of different early virus functions.