Eucaryotic cells contain two complete genetic systems, one based on nuclear DNA and the other on cytoplasmic DNA . The study of these systems has been greatly facilitated by the existence of specific inhibitors . One such inhibitor is the trypanocidal drug, ethidium bromide (Short, Peak, and Watkins, 1953) . Application of the drug to trypanosomes in vitro causes alterations in the structure of...

Nieders~chsisches Institut ffir Peptid-Forschung GmbH, D-30625 Hannover, Germany PCR amplification of sequences from genomic DNA often yields multiple nonspecific bands, especially if the amplified regions are rich in guanosine and cytosine. G/C-rich sequences can cause hairpin loop structures that potentially give rise to problems for in vitro DNA amplification. In addition to this, G/Crich pr...

Received December 29,1975 SUMMARY: We have developed a rapid electrophoretic technique for performing ethidium bromide dye titrations in cylindrical 0.7% agarose gels. The technique was used to analyze the extent of supercoiling in circular covalently closed SV40, ColEl, and pSClO1 DNA. We have estimated the superhelical densities of SV40, ColEl, and pSClO1 DNA to be -0.050, -0.078, and -0.085 ...

The synthesis of mitochondrial DNA (mDNA) in HeLa cells is selectively inhibited by relatively low concentrations of ethidium bromide. After exposure of cells to strongly inhibitory concentrations of the drug, the apparent superhelix density of mDNA is rapidly increased, as judged by its buoyant density in CsCl in the presence of ethidium bromide. Mitochondrial DNA synthesized in the presence o...

Nucleic acids that have been subjected to electrophoresis through agarose gels may be detected by staining and visualized by illumination with 300-nm UV light. Methods for staining and visualization of DNA using either ethidium bromide or SYBR Gold are described here. The most convenient and commonly used method to visualize DNA in agarose gels is staining with the fluorescent dye ethidium brom...

Quinoxaline-2, 3-dione obtained from cyclocondensation reaction of o-phenylene diamine with oxalic acid was reacted with three different ketones and formaldehyde to give the corresponding Mannich bases in satisfactory yield. Their structures were confirmed by using (1)H NMR, IR, and mass analysis. In pharmacological evaluation, the synthesized compounds showed its curative effect against ethidi...

We studied the interaction of ethidium bromide with rye and calf thymus chromatin. Both types of chromatin have the same dye accessibility, which is about 50% of that of DNA. From this result we conclude that the molecular structure of these two chromatins is similar. For rye, the extraction of H1 produces no change in the binding of ethidium bromide. The subsequent extraction of H2A and H2B pr...