Dr. Julin's lab is studying enzymes that participate in DNA repair in the bacterium Deinococcus radiodurans, and the RecBCD enzyme from Escherichia coli. Living organisms are under constant assault by environmental agents that damage their DNA, including radiation and reactive chemicals. These agents lead to formation of damaged bases and DNA strand breaks which, if unrepaired, can lead to cell death, mutation, and cancer in humans. Organisms defend themselves against this onslaught by deploying a variety of DNA repair and recombination enzymes that are able to undo the damage and restore the DNA to its original undamaged state.