S.C. Maitra

On the existence of independently melting subunits in a copolymeric DNA and their statistical distribution

Abstract Using a modified Ising model proposed earlier ( Montroll & Goel, 1966 ) for interpreting the data on the thermal denaturation of DNA molecules with certain reasonable approximations, it is shown that in Escherichia coli and calf thymus DNA, during thermal denaturation in SSC solution, bondings between nucleotides in the two strands break in groups of about 40 bonds, the group rich in AT melting earlier than the one rich in GC. In addition, the relative frequencies of groups of various GC percentages are calculated, thus providing some statistical information about the base sequence in natural DNA molecules.