| Abstract: | A DNA-dependent RNA polymerase was solubilized from sucrose gradient isolated, DNase-treated mitochondria of Drosophila melanogaster. The isolated mitochondria were not detectably contaminated with nuclear DNA as shown by CsCl gradient centrifugation and polylysine Kieselguhr chromatography. The detergent-solubilized RNA polymerase was sensitive to rifampicin, resistant to alpha-amanitin, had an apparent molecular mass of about 60 kilodaltons, and displayed a tendency to aggregate, both in crude extracts or when purified. The mitochondrial RNA polymerase could be distinguished from nuclear RNA polymerases on the basis of size, salt optima, rifampicin sensitivity, and alpha-amanitin resistance. |
