In the 31 March 2005 issue of Nature (Vol. 434, No. 7033, pp 612-618), researchers report the chemical structure of an enzyme vital for repairing routine damage to our DNA that is caused by oxidative damage. Their snap-shot of the protein captures it in the act of testing DNA for errors.
When oxidants attack DNA they can subtly alter the molecular building block guanine (G), creating a variation called 8-oxoguanine that can cause permanent mutations. The enzyme 8-oxoguanine DNA glycosylase 1 (OGG1) recognizes and repairs 8-oxoguanine, and mutations in it have been linked to lung and possibly kidney cancer.
By determining the X-ray structure of human OGG1 bound to undamaged DNA, Gregory Verdine and his colleagues reveal how the enzyme efficiently scans for abnormal guanine residues embedded in a vast expanse of normal DNA, and how it removes them from the DNA helix without damaging normal bases.
Gregory Verdine (Harvard University, Cambridge, MA, USA)
Sheila S. David (University of Utah, Salt Lake City, UT, USA)
(C) Nature press release.
Message posted by: Trevor M. D'Souza