Fractionation of Deoxyribonucleoprotein

1 The extraction of denatured desoxyribonucleoprotein, from calf thymus, with successive quantities of 0.6 N sodium chloride solution has been found to yield nucleic acid fractions (DNA) with varying base ratios, the initial extracts being richer in guanine and cytosine. 2 Some physical-chemical properties of these DNA fractions have been determined. 3 The histones extracted by this means have also been examined and it has been found that the earlier fractions show a relatively high content of lysine, while the later fractions are richer in arginine. However, the lysine rich histone is apparently not firmly attached to the DNA and may have been extracted independently.