Comparison of partial denaturation maps with the known sequence of simian virus 40 and phi X174 replicative form DNA.

Electron microscope partial denaturation maps of two viral DNAs, simian virus 40 and φX174 replicative form, have been obtained. A simple computer program has been developed to predict denaturation maps from any given DNA sequence, based on the percentage of A · T base-pairs along the molecule. Maps constructed from the SV40 DNA and φX174 replicative form DNA base sequence show a good correlation with the experimental maps. The results show that the regions of a DNA molecule that denature first are, in fact, those regions with the highest content of adenine and thymine base-pairs.