Purification of DNA polymerase II, a distinct DNA polymerase, from Saccharomyces cerevisiae.

摘要: Yeast DNA polymerases I and III have been well characterized physically, biochemically, genetically immunologically. polymerase II is present in very small amounts, only partially purified preparations available for characterization, making comparison with difficult. Recently, we shown that are distinct (Sitney et al., 1989). In this work, show also from I, since can be equal amounts wild-type mutant strains completely lacking activity. Thus, yeast contains three major nuclear polymerases. The core catalytic subunit of was to near homogeneity using a reconstitution assay. Two factors stimulate the were identified used monitor activity during purification analysis. predominant species most highly preparation 132,000 Da. However, gels suggest 132,000-Da form probably an active proteolytic fragment derived 170,000-Da protein. fractions contain 3'----5'-exonuclease purifies at constant ratio final two steps. does not copurify primase