11/03/2008
Radiation Resistance of Microbe Could be Due to Activities of Hydrolase Proteins
Summary
A research team from Brookhaven National Laboratory the University of Toronto and the Pacific Northwest National Laboratory used state-of-the-art nuclear magnetic resonance (NMR) spectroscopy capabilities at the William R. Wiley Environmental Molecular Sciences Laboratory (EMSL), a DOE Scientific User Facility located in Richland, Washington, to probe the activity of a hydrolase protein from a microorganism that is highly resistant to radiation. The microbe, Deinococcus radiodurans, can survive thousands of times more radiation exposure than a human, but the mechanism for this astounding resistance is not understood. One mechanism could be that a group of proteins called Nudix hydrolases protect cells by binding to specific forms of cellular metabolites called nucleosides. Using the NMR spectroscopic capabilities at EMSL, the research team was able to study the molecular binding of the Nudix hydrolase DR_0079, with nucleosides in real time. Unlike other hydrolases, DR_0079 binds to nucleoside diphosphate and converts it into a form that cannot lead to mutations in deoxyribonucleic acid (DNA). Understanding the molecular basis for the radiation resistant properties of D. radiondurans could lead to strategies that protect humans from the effects of ionizing radiation, or to novel bioremediation strategies for DOE sites with radionuclide contamination. The research was supported by the Office of Science, Genome Canada, the Ontario Research and Development Challenge Fund, and the National Institutes of Health Protein Structure Initiative.
References
Buchko GW, O Litvinova, H Robinson, AF Yakunin, and MA Kennedy. 2008. “Functional and Structural Characterization of DR_0079 from Deinococcus radiodurans, a Novel Nudix Hydrolase with a Preference for Cytosine (Deoxy) Ribonucleoside 5′-Di- and Triphosphates.” Biochemistry 47:6571-82.