Tightly complexed with DNA nonhistone chromatin proteins from hamster Kirkman-Robbins hepatoma

Two groups of nonhistone chromatin proteins tightly bound to DNA were isolated from hamster liver and Kirkman-Robbins hepatoma with the use of hydroxyapatite columns: 1. NP proteins which can be briefly defined as nonhistone chromatin proteins, nondissociable from DNA in 5 M urea, and 2. a group of proteins nondissociable in 2 M KCl and thus believed to be nonelectrostatically bound to DNA. The proteins were characterized by their amino acid analysis, SDS-polyacrylamide gel electrophoresis and their influence on template activity of DNA. Some differences in electrophoretic patterns and template activity inhibition were found between the latter group of proteins from liver and hepatoma.