A New Group of Chromatin‐Associated Proteins with a High Content of Acidic and Basic Amino Acids

A new group of chromatin‐associated proteins having a high content of acidic and basic amino acids have been isolated from the 0.35 M NaCl‐extractable proteins from calf thymus. This new group, designated “high‐mobility group” proteins have been partially separated and some interesting new proteins identified. One such protein contains over 55% acidic and basic amino acids.