Plant Pathology Department


Date of this Version



Published in APPLIED AND ENVIRONMENTAL MICROBIOLOGY, 0099-2240/97/$04.0010 Apr. 1997, p. 1551–1556 Vol. 63, No. 4 Copyright © 1997, American Society for Microbiology. Used by permission.


The bacteriophage T4 denV gene encodes a well-characterized DNA repair enzyme involved in pyrimidine photodimer excision. We have discovered the first homologs of the denV gene in chlorella viruses, which are common in fresh water. This gene functions in vivo and also when cloned in Escherichia coli. Photo-damaged virus DNA can also be photoreactivated by the host chlorella. Since the chlorella viruses are continually exposed to solar radiation in their native environments, two separate DNA repair systems, one that functions in the dark and one that functions in the light, significantly enhance their survival.