Weinbauer, M.G., Wilhelm, S.W., Suttle, C.A., Garza, D.R. 1997. Photoreactivation Compensates for UV Damage and Restores Infectivity to Natural Marine Viral Communities. Applied and Environmental Microbiology 63:2200-2205.

We investigated the potential for photoreactivation to restore infectivity to sunlight-damaged natural viral communities in offshore (chlorophyll a, < 0.1 mg liter^-1), coastal (chlorophyll a, ca. 0.2 mg liter^-1) and estuarine waters (chlorophyll a, ca. 1 to 5 mg liter^-1) of the Gulf of Mexico. In 67% of samples, the light-dependent repair mechanisms of the bacterium Vibrio natriegens restored infectivity to natural viral communities which could not be repaired by light-independent mechanisms. Similarly, exposure of sunlight-damaged natural viral communities to >312 nm sunlight in the presence of the natural bacterial communities, restored infectivity to between 21 and 26 % of sunlight-damaged viruses in oceanic waters and between 41 and 52 % of the damaged viruses in coastal and estuarine waters. Wavelengths between 370 and 550 nm were responsible for restoring infectivity to the damaged viruses. These results indicate that light-dependent repair, probably photoreactivation, compensated for a large fraction of sunlight-induced DNA damage in natural viral communities, and is potentially essential for the maintenance of high concentrations of viruses in surface waters.