EN
In vitro binding of Hg2+ by rat liver chromatin was studies. Mercury was mainly bound by chromatin nonhistone proteins and, to a considerably lesser extent, by histones and DNA. Not only type and quantity of ligands, but also the structure of the chromatin complex were essential for metal binding. High mercury-binding capacity was observed for loosely packed euchromatin or chromatin decondensed by selective extraction of H1 and core histones. The opposite effect, i. e. masking of mercury-binding sites was observed during reconstitution of deoxyribonucleoprotein complexes.