Chlorella virus-encoded deoxyuridine triphosphatases exhibit different temperature optima.

ABSTRACT: A putative deoxyuridine triphosphatase (dUTPase) gene from chlorella virus PBCV-1 was cloned, and the recombinant protein was expressed in Escherichia coli. The recombinant protein has dUTPase activity and requires Mg(2+) for optimal activity, while it retains some activity in the presence of other divalent cations. Kinetic studies of the enzyme revealed a K(m) of 11.7 microM, a turnover k(cat) of 6.8 s(-1), and a catalytic efficiency of k(cat)/K(m) = 5.8 x 10(5) M(-1) s(-1). dUTPase genes were cloned and expressed from two other chlorella viruses IL-3A and SH-6A. The two dUTPases have similar properties to PBCV-1 dUTPase except that IL-3A dUTPase has a lower temperature optimum (37 degrees C) than PBCV-1 dUTPase (50 degrees C). The IL-3A dUTPase differs from the PBCV-1 enzyme by nine amin

SUBMITTER: Zhang Y 

PROVIDER: S-EPMC1181562 | biostudies-literature | 2005 Aug

REPOSITORIES: biostudies-literature