Abstract: | Highly purified preparations of (ADP-ribose) polymerase were obtained from calf testis and thymus by chromatography on DNA-cellulose, hydroxyapatite and gel filtration. It was shown that the enzymes isolated from both sources under identical conditions have similar values of Mr, Vmax and Km in the reactions of autoribosylation and poly(ADP-ribosylation) of histone H1 as well as similar pH-dependencies of the catalyzed reactions. |