Induction of Strand Break in DNA by Reducing Sugar Phosphates

Abstract

The DNA breakage action of sugars was investigated by agarose gel electrophoresis of phage øX174 superhelical duplex DNA. Some reducing sugar phosphates such as D-fructose 6-phosphate, 2-amino-2-deoxy-D-glucose 6-phosphate and D-ribose 5-phosphate induced single strand breaks in øX174 superhelical duplex DNA. Cu²⁺ stimulated the DNA strand break. EDTA, superoxide dismutase, catalase and oxygen radical scavengers inhibited the DNA strand break. The DNA strand break was, therefore, caused by oxygen radicals generated during the autoxidation of reducing sugar phosphates. Other reducing sugar phosphates and many common reducing sugars which have a carbonyl group also induced strand breaks in øX174 superhelical duplex DNA in the presence of Cu²⁺.