Protective Qualities of UV-resistant Bacteria

Abstract

Ultraviolet radiation causes detrimental effects on the cell by mutating its DNA. Micrococcus luteus and Micrococcus radiophilus are two bacterial species known to be able to withstand high levels of UV radiation. However, it is unknown if they have any protective effects on other cells, like Escherichia coli. Using UVB radiation from a light box, minimum lethal doses (MLD) were determined for M. luteus, M. radiophilus, and E. coli. The MLDs of the Micrococcus species were substantially higher than the MLD of E. coli. E. coli was mixed with the Micrococcus species and exposed to UV radiation to test for protective effects. It was found that E. coli was able to grow past its MLD in a few cases with both M. luteus, and M. radiophilus. However, it was noted that exact timing was difficult to obtain with our methods. It was found that the E. coli colonies that did grow in higher UV exposure were usually surrounded by a Micrococcus species, potentially showing protection. Exploring microbes for their UV protective qualities may provide an alternative for chemical containing sunscreens, offering a potentially safer product for both people and the environment.