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Substrate, metal and template effects on inhibition of bacteriophage-qbeta ribonucleic acid polymerase by ortho- and pyro-phosphate.

ABSTRACT: Two reactions of bacteriophage-Qbeta RNA polymerase with synthetic templates were characterized and used to study the effects of substrate, metal and template on inhibition by Pi and PPi. Analysis of the poly(C)-dependent reaction yielded results on kinetics, GTP-dependence, preference for Mn2+ over Mg2+, and Michaelis constants for template similar to those in the literature. New data are provided for the poly(U2,C)-dependent reaction. Our results suggest that GTP and Mn2+ can form relatively stable complexes with the polymerase and that such complexes change the interaction of the enzyme with the inhibitors, Pi and PPi.

SUBMITTER: Brooks RR

PROVIDER: S-EPMC1184020 | biostudies-other | 1978 Jun

REPOSITORIES: biostudies-other

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