Mathematical Modeling of Open States in Double Stranded DNA Molecule Depending on 2H/1H Ratio

The evaluation results of the possible deuterium atoms effect on the DNA base pair opening are presented in the article. The cause of these processes is the replacement of protium with deuterium atom due to the increase of energy required to break the hydrogen bond. These processes can be studied by method of mathematical modeling, with account of open states between base pairs being the key condition of the adequacy of the mathematical model of the DNA. The experiment data show that the presence of deuterium in a chain of nucleotides can cause - depending on the value of hydrogen bond disruption energy - both increase and decrease in probability of open states occurrence. For example: hydrogen bond disruption energy of 0.358·10 -22 n·m, non-zero probability of open states occurrence is observed in case of the absence of deuterium in the molecule, and with hydrogen bond disruption energy of 0.359·10 -22 n·m or more such probability equals zero. Also, when one deuterium atom is present in a molecule, non-zero probability is observed even with hydrogen bond disruption energy equal to 0.368·10 -22 n·m (i.e. more than 0.358·10 -22 n·m). Thus participation of deuterium atoms in the formation of hydrogen bonds of double helixes of a DNA molecule can cause the changes in the time required for transfer of genetic information, which can explain the effect of even minor deviations in deuterium concentration in a medium on metabolic processes in a living system.