Three forms of DNA-dependent RNA polymerase have been separated by chromatography of extracts of yeast-like cells and mycelium of the dimorphic fungus Mucor rouxii. Each of the three eznymes has been purified by means of protamine sulfate precipitation, ion exchange chromatography, affinity chromatography, and velocity sedimentation. Electrophoresis under denaturing conditions showed difference...

phosphate intermediates, judging from lack of contribution to adenine, uracil, and cytosine nucleosides in RNA and DNA. The group of enzymatic activities that catalyze the conversion of guanine and guanosine to guanosine triphosphate (namely, guanosine kinase, purine nucleoside phosphorylase, purine nucleoside monophosphate kinase, nu cleoside diphosphate kinase, and purine nucleoside triphosph...

A growth factor (HGF) stimulating DNA synthesis of adult rat hepatocytes in primary culture was found in rat platelets. HGF was purified from rat platelets to homogeneity by a three-step procedure: stimulation of its release from platelets by thrombin, cation-exchanger fast protein liquid chromatography on a Mono S column, and heparin-Sepharose chromatography. HGF was clearly distinguishable fr...

Chromatin was prepared by two dif ferent methods f rom isolated nuclei of Gyrodinium cohnii ( Cryptothecodinium cohnii) and Peridinium trochoideum. These isolation procedures are different from those generally used to prepare eukaryote chromatin, because the latter do not work for dinoflagellate chromatin. The chemical composition of this chromatin is similar for both methods of preparation and...

DNA damaging agents such as ionizing radiation or chemotherapy are frequently used in oncology. DNA damage response (DDR)-triggered by radiation-induced double strand breaks-is orchestrated mainly by three Phosphatidylinositol 3-kinase-related kinases (PIKKs): Ataxia teleangiectasia mutated (ATM), DNA-dependent protein kinase (DNA-PK) and ATM and Rad3-related kinase (ATR). Their activation prom...

The dose dependency of the binding of benzo(a)pyrene (BaP) with DNA of mouse epidermis was investigated. BaP conjugated epidermab DNA was isolated and enzymatically degraded to deoxyribonucleosides. The BaP-DNA adducts were separated by Sephadex LH-20 column or high-perform ance liquid chromatography. Two major BaP-DNA adducts were found. One was in the region of the ebution profile that contai...

Brown bullheads (Ictalurus nebulosas) were sampled from sites in the Buffalo and Detroit Rivers where fish are exposed to high levels of sediment bound polycyclic aromatic hydrocarbons, and suffer from an elevated frequency of liver cancer. DNA was isolated from the livers of these wild fish and from control specimens which were raised in clean aquariums. DNA was enzymatically digested to norma...

The dose dependency of the binding of benzo(a)pyrene (BaP) with DNA of mouse epidermis was investigated. BaP-conjugated epidermal DNA was isolated and enzymatically degraded to deoxyribonucleosides. The BaP-DNA adducts were separated by Sephadex LH-20 column or high-performance liquid chromatography. Two major BaP-DNA adducts were found. One was in the region of the elution profile that contain...

In vivo 4-hydroxyamino[2-3H]quinoline 1-oxide-modified DNA and in vitro 4-acetoxyamino[2-3H]quinoline 1-oxide-modified DNA were enzymatically hydrolyzed, and the hydrolysates were analyzed by high-performance liquid chromatography. The two patterns were compared, and we showed that all of the high-performance liquid chromatography peaks which were recovered from in vivo-modified DNA were presen...