Related Experiment Video
Updated: Jun 19, 2026
In vitro tRNA Methylation Assay with the Entamoeba histolytica DNA and tRNA Methyltransferase Dnmt2 (Ehmeth) Enzyme
Published on: October 19, 2010
Partial purification and characterization of Trichomonas vaginalis DNA topoisomerase II
Somphong Sithiprom1, Songsak Petmitr, Porntip Chavalitshewinkoon-Petmitr
1Department of Protozoology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
Abstract:
DNA topoisomerases regulate conformational changes in DNA topology by catalyzing the breakage and rejoining of DNA strands during the cell cycle. These processes are essential for the multiplication of cells, and inhibition of these reactions stops cell division and cell growth. Drug resistance to Trichomonas vaginalis, a common sexually transmitted protozoan parasite, is increasing worldwide, and DNA topoisomerase II may provide a new target for anti-trichomonal drug development. In this study, T. vaginalis DNA topoisomerase II was partially purified from a large scale axenic culture using fast protein liquid chromatography with a yield of 0.16% and 17-fold purification. The partially purified enzyme was strictly dependent on ATP and Mg2+ with optimal concentration of 1 and 10 mM respectively for relaxation activity. T. vaginalis DNA topoisomerase II activity was inhibited by m-amsacrine (m-AMSA) and ofloxacin at minimum inhibitory concentration (MIC) of 250 microM. At this concentration, ciprofloxacin showed incomplete inhibition whereas metronidazole was inactive. DW6, a DNA quadruplex binder, was the most active compound with MIC of 62.5 microM, suggesting the potential for development of such compounds as selective anti-trichomonal drugs in the future.
Insights
This study identifies DNA topoisomerase II from Trichomonas vaginalis as a potential drug target. Inhibiting this enzyme shows promise for developing new anti-parasitic drugs against drug-resistant infections.
Area of Science:
- Biochemistry
- Parasitology
- Drug Discovery
Background:
- DNA topoisomerases are crucial for DNA topology regulation and cell division.
- Increasing drug resistance in Trichomonas vaginalis necessitates novel therapeutic targets.
- DNA topoisomerase II presents a potential target for anti-trichomonal drug development.
Purpose of the Study:
- To partially purify and characterize DNA topoisomerase II from Trichomonas vaginalis.
- To evaluate the inhibitory effects of various compounds on T. vaginalis DNA topoisomerase II activity.
- To explore the potential of DNA topoisomerase II as a target for new anti-trichomonal agents.
Main Methods:
- Partial purification of T. vaginalis DNA topoisomerase II using fast protein liquid chromatography.
- Assay of enzyme activity dependence on ATP and Mg2+.
- Determination of minimum inhibitory concentrations (MICs) of various drugs and compounds against the enzyme.
Main Results:
- T. vaginalis DNA topoisomerase II was purified 17-fold, showing strict dependence on ATP and Mg2+.
- m-amsacrine (m-AMSA) and ofloxacin inhibited the enzyme at 250 microM.
- DW6, a DNA quadruplex binder, demonstrated significant activity with an MIC of 62.5 microM.
Conclusions:
- T. vaginalis DNA topoisomerase II is a viable target for anti-parasitic drug development.
- Compounds like DW6 show potential for selective anti-trichomonal drug development.
- Targeting DNA topoisomerase II could offer a new strategy against drug-resistant Trichomonas vaginalis infections.
Related Concept Videos
01:18Trichomoniasis
01:34DNA Isolation
01:24DNA Isolation