Evidence for DNA Polymerase‐α and ‐β Activity in Sugar Beet

Abstract

AbstractDNA polymerase preparations from incubated sugar beet (Beta vulgaris) root tissue exhibited multiple activities following DEAE‐cellulose chromatography and glycerol density gradient centrifugation (600‐fold purification). The two major polymerase activities eluted from DEAE‐cellulose differed in heat lability, pH and Mg2+ optima, and in response to ethanol, p‐hydroxymercuribenzoate, and N‐ethylmaleimide. Further purification by glycerol gradient centrifugation indicated the presence of a low molecular weight molecule (3.4 S), heterogeneous larger molecules (6.2, 6.8 S), and apparent aggregates (11–11.5 S). This investigation indicates similarities between sugar beet polymerases and the small (β) and large (α) molecular weight polymerases from mammalian systems.