Speaker: Rodney L. Levine, NIH, Bethesda, MD, USA

Oxidative Modification of Proteins - in cellular signaling and in stress

Because eukaryotic cells depend on molecular oxygen for normal metabolism, they generate reactive oxygen species (ROS) that can cause multiple forms of cellular stress and damage. For several years, Dr. Levine has focused his research on the identification of oxidative modifications of proteins. He is interested in the conditions that give rise to modifications in which amino acids are modified, and the impact those modifications have on enzymatic function or structural integrity.

More recently, Dr. Levine and his colleagues have found that methionine sulfoxide reductase catalyzes oxidation and reduction of methionine residues bidirectionally. This finding opens the door to a role for oxidative modification of methionine as a cellular signaling mechanism. Whereas ROS production has been viewed as uniformly deleterious to cellular function, it is now clear that cells actually require a certain level of oxidants for optimal function. Dr. Levine is pursuing the hypothesis that oxidative modifications of proteins are not always a negative effect of stress, but also participate in normal cellular signaling.

Host: Elzbieta Glaser