Electrophoresis of the nucleic acids

Abstract

Abstract A zone electrophoresis apparatus using ultraviolet, optics has been constructed to study nucleic acids at concentration less than 0.004%. Native DNA has a mobility about 15% higher than denatured DNA over a range of conditions of pH and ionic strength. DNA's from different sources have closely similar mobilities. A study of a molecular weight series of DNA indicates that the mobility is constant in the molecular weight range of 2.5 × 10 5 to 1.3 × 10 8 . DNA mobilities change in the expected way with pH but the fractional change in mobility is less than the change in charge calculated by titration curves. A small decrease in mobility accompanies an increase in ionic strength. RNA's from various sources have mobilities slightly lower than denatured DNA except for s‐RNA which travels slightly faster.