Parasitology Research

, Volume 106, Issue 5, pp 1257–1262 | Cite as

Evaluation of drug effects on Toxoplasma gondii nuclear and plastid DNA replication using real-time PCR

  • Qing ZhaoEmail author
  • Ming Zhang
  • Lingxian Hong
  • Kefu Zhou
  • Yuguang Lin
Rapid Communication


Toxoplasma gondii Nicolle and Manceaux, 1908 is a unicellular protozoan that can infect a broad spectrum of organisms including humans. In addition to a nuclear genome, it also carries a circular DNA within a plastid-like organelle (apicoplast) and a linear genome within its mitochondria. The plastid organelle has been shown to be the target of various anti-parasitic drugs or antibiotics. To evaluate the effects of agents on the DNA replication of T. gondii, we tested six drugs (ciprofloxacin, acetylspiramycin, clindamycin, azithromycin, artemether, and sulfadiazine) on the parasite cultured in Hela cells. After drug treatment for 48 h, the parasite growth and DNA replication were evaluated and quantitated using TaqMan real-time quantitative PCR with oligonucleotide primers synthesized based on a gene from the apicoplast genome (ycf24, Genbank accession no. U87145) and a gene from the nuclear genome (uprt, Genbank accession no. U10246). Our results showed that ciprofloxacin was the most effective in inhibiting the replication of the plastid DNA after 48 h drug treatment, with a reduction of 22% in the copy number of the plastid DNA. Artemether was the most effective drug in suppressing the proliferation of tachyzoites. This study also demonstrates that real-time quantitative PCR is a simple and useful technique for monitoring parasite growth and DNA replication.


Azithromycin Clindamycin Plastid Genome Sulfadiazine Toxoplasma Gondii 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Thanks Dr. Liu Jie (Institute of Pathogenic biology, Nanhua University, China) for his kindly help in data analysis and Dr. Su Xinzhuan (NIH, USA) for his constructive suggestions in revising the manuscript.


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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Qing Zhao
    • 1
    Email author
  • Ming Zhang
    • 2
  • Lingxian Hong
    • 1
  • Kefu Zhou
    • 1
  • Yuguang Lin
    • 1
  1. 1.School of Life SciencesXiamen UniversityXiamenChina
  2. 2.Institute for Biomedical ResearchXiamen UniversityXiamenChina

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