Biphasic effect of polyamines on chromatin-bound histone deacetylase

Abstract

Calf thymus chromatin preparations contain a bound histone deacetylase. The activity of the deacetylase is increased by addition to the reaction mixture of 0.1 to 1 m m polyamine. Further increase in polyamine levels cause a progressive inhibition of enzyme activity. This biphasic action was shown to result from two opposite activities. First, low levels of polyamines are able to release several-fold greater amounts of enzyme from the bound state to free solution. Second, the free enzyme activity is progressively inhibited by polyamines from 0.1 to 20 m m. The combination of the two activities accounts for a peak of activity at around 1 m m polyamine.