Reverse transcriptase-associated ribonuclease H does not require zinc for catalysis.

M J Modak; A Srivastava

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PubMed · 86544

Reverse transcriptase-associated ribonuclease H does not require zinc for catalysis.

M J Modak·A Srivastava

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Abstract

omicron-Phenanthroline, a zinc chelating agent, is known to inhibit the DNA polymerase activity of cellular DNA-dependent and viral RNA-dependent DNA polymerases. We find that omicron-phenanthroline does not inhibit the reverse transcriptase-associated RNase H activity of retroviruses. Kinetic studies, using DNA template-primers as an inhibitor of RNase H, suggest that zinc does not play any role in template-primer binding by reverse transcriptase. These results also indicate a distinct binding site for the template and triphosphate substrates. Cellular RNase H from calf thymus and RNase H-II from Rauscher leukemia virus are likewise resistant to omicron-phenanthroline inhibition, implying non-involvement of zinc in the nucleic acid hydrolysis by these enzymes.

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Avian Myeloblastosis Virus DNA-Directed DNA Polymerase Endonucleases Kinetics Oncogenic Viruses Phenanthrolines RNA-Directed DNA Polymerase Ribonucleases Zinc Journal Article Research Support, U.S. Gov't, P.H.S.

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M J Modak, A Srivastava. 1979-06-10. Reverse transcriptase-associated ribonuclease H does not require zinc for catalysis.. https://pubmed.ncbi.nlm.nih.gov/86544/

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