title: Partial purification and properties of calf thymus deoxyribonucleic acid dependent RNA polymerase III.
abstract: DNA-dependent RNA polymerase III (nucleosidetriphosphate: RNA nucleotidyltransferase, EC 2.7.-7.6) has been isolated and partially purified from calf thymus tissue. Significant amounts of enzyme III are present in this tissue (up to 15% of the total activity of thymus homogenates). This enzyme has been characterized with respect to its chromatographic properties, broad ammonium sulfate optimum (0.04-0.2 M), template requirements, divalent metal optima, and its unique alpha-amanitin sensitivity (50% inhibition of activity occurring at an alpha-amanitin concentration of 10 mug/ml).
mesh_terms: D000546:Amanitins / Q000494:pharmacology; D000645:Ammonium Sulfate; D000818:Animals; D002417:Cattle; D002499:Centrifugation, Density Gradient; D002852:Chromatography, Ion Exchange; D004247:DNA; D012321:DNA-Directed RNA Polymerases / Q000302:isolation & purification* / Q000378:metabolism; D003609:Dactinomycin / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D007527:Isoenzymes / Q000302:isolation & purification / Q000378:metabolism; D007700:Kinetics; D012995:Solubility; D013698:Templates, Genetic; D013950:Thymus Gland / Q000201:enzymology*
chemical_list: D000546:Amanitins; D007527:Isoenzymes; D003609:Dactinomycin; D004247:DNA; D012321:DNA-Directed RNA Polymerases; D000645:Ammonium Sulfate