• 1 January 1977
    • journal article
    • research article
    • Vol. 37 (6), 1598-1601
Abstract
A Mg independent dUTPase was found in Yoshida sarcoma cells but not in normal rat liver. The phosphatase is specific for dUDP and dUTP, and its Km for dUTP is 2.7 .times. 10-7 M. The enzyme was not inhibited by F and required no divalent cations. It differs from known nucleotide phosphatases. dUMP, which is detectable in a crude extract of normal rat liver, could not be detected in an extract of Yoshida sarcoma cells. With hydroxylapatite column chromatography of the extract, dUMP kinase activity as high as that in normal rat liver was found in fractions separated from the phosphatase activity. The absence of detectable dUMP kinase activity in the crude extract of Yoshida sarcoma cells is due to the presence of this nucleotide phosphatase.