DNA Topoisoerases

UNCP Author/Contributor (non-UNCP co-authors, if there are any, appear on document)
William M. Siders (Creator)
The University of North Carolina at Pembroke (UNCP )
Web Site: http://www.uncp.edu/academics/library
David Kuo

Abstract: Gel electrophoresis was performed on six known mutagens: MMS, EMS, Mtx, Caf, AHA, and HyC, to test the affect each would have on topo I and topo II enzymes controlling the topological states of DNA. Each compound/DNA/enzyme mixture was prepared three different ways in order to localize the compound' affect i.e. whether the compound affected the DNA or the enzyme. Each of the gels was divided into two parts to test the affect of sodium dodecyl sulfate (SDS), used to denature proteins, upon the cleavable complex. SDS is commonly used in the mixtures which halt the enzymatic reactions. In each of the gels the top half contained no SDS while the bottom part was treated with SDS. In both cases identical conditions were used. The results was the SDS had no apparent affect on the cleavable complex. Each of the six mutagens caused enzymatic inactivity in the third mixture; which consisted of adding the compound and enzyme first and then adding DNA. Thus, the compound directly affected the enzyme causing it to be unable to bind to the DNA. Two of the six compounds, caffeine and hycanthone, caused inactivity in the other two mixtures. This however can be explained by the fact that each intercalates the DNA.

Additional Information

Language: English
Date: 1990
DNA, Mutagen, Electrophoresis, Enzyme, Sodium Dodecyl Sulfate, Enzymatic Activity

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