Determining the cellular targets of reactive oxygen species in Borrelia burgdorferi

The response of Borrelia burgdorferi to the challenge of reactive oxygen species (ROS) is a direct result of its limited biosynthetic capabilities and lack of biologically significant levels of intracellular Fe. In other bacteria, the major target for oxidative damage is DNA as a consequence of the reaction of "free" intracellular with ROS through the Fenton reaction. Therefore, cellular defenses in these bacteria are focused on protecting this essential cellular component. This does not seem to be the case for B. burgdorferi. In this chapter, we describe methods that were used to analyze the potential targets for ROS in B. burgdorferi. Surprisingly, membrane lipids (e.g., linoleic and linolenic acids) derived from host are the major target of ROS in the Lyme disease spirochete.