Quantitation of different dma conformations in purified genomic 25-40 million year old bee (proplksbia dokuhcaka) DNA

The objectiva of thia project warn to examine for the presence of different genomic DNA conformation, isolated from cells of a prehistoric organism: 25-40 million year old bee. Ancient bee DNA was generoualy given to ua by Dr. R. Cano, California Polytechnic State University, San Luis Obispo, Ca. Our group wanted to identify any poeeible degradation [denatured single-stranded (as-) DNA] of the ancient DNA, and to determine the right-handed B-DNA to lefthanded Z-DNA transitions. Anti-double-stranded (da-} BDNA, anti-ds-Z-DNA and anti-sa-DNA antibodies were employed to analyze the ancient DNA. Fluorescence KLISA waa used to quantitat the interactions between DNA and antibody probes. Our data shows that B-DNA, aa-DNA and Z-DNA are present and can be quant itated. Therefore, the same antigenic determinants available today were preaent in ancient DNA. When compared to our positive controls (DNA from present day organisms), we observed more ss-DNA, and less da-B-DNA and ds-Z-DNA immunoreactivity in the prehistoric DNA samples. Ancient DNA probably contains damage from oxidation, but overall it can survive time-dependent decay beyond 25-40 million years. He conclude that DNA can remain a dynamic molecule with the ability to undergo helical (conformational) transitions.