Antifolate screening using yeast expressing Plasmodium vivax dihydrofolate reductase and in vitro drug susceptibility assay for Plasmodium falciparum

• Published in: Molecular and biochemical parasitology Vol. 156; no. 1; pp. 89 - 92
• Main Authors: Djapa, Liselotte Yimga, Basco, Leonardo K., Zelikson, Ruth, Rosowsky, Andre, Djaman, Joseph Allico, Yonkeu, Jeanne Ngogang, Bolotin-Fukuhara, Monique, Mazabraud, André
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.11.2007; Elsevier
• Subjects: Animals; Antifolate drugs; Biochemistry, Molecular Biology; Drug resistance; Folic Acid Antagonists; Folic Acid Antagonists - pharmacology; Inhibitory Concentration 50; Life Sciences; Malaria; Microbiology and Parasitology; Mutation; Parasitic Sensitivity Tests; Plasmodium falciparum; Plasmodium falciparum - drug effects; Plasmodium falciparum - growth & development; Plasmodium falciparum in vitro culture; Plasmodium vivax; Plasmodium vivax - enzymology; Plasmodium vivax - genetics; Quinazolines; Quinazolines - pharmacology; Saccharomyces cerevisiae; Saccharomyces cerevisiae - drug effects; Saccharomyces cerevisiae - enzymology; Saccharomyces cerevisiae - genetics; Tetrahydrofolate Dehydrogenase; Tetrahydrofolate Dehydrogenase - genetics; Tetrahydrofolate Dehydrogenase - metabolism; Yeast; Plasmodium vivax; Yeast; Malaria; Antifolate drugs; Drug resistance; Plasmodium falciparum in vitro culture
• ISSN: 0166-6851; 1872-9428
• DOI: 10.1016/j.molbiopara.2007.07.009

The presence of homologous point mutations in the dhfr gene in Plasmodium vivax and Plasmodium falciparum is associated with resistance to antifolate drugs. The spread of antifolate resistance encouraged research for novel antifolate drugs active against both wild-type and dhfr-mutant strains of malaria parasites. Because P. vivax cannot be easily maintained in culture, we transformed a Saccharomyces cerevisiae DHFR-deleted mutant to express wild-type P. vivax dhfr gene and its mutant forms. Twenty-five dicyclic and tricyclic 2,4-diaminopyrimidine derivatives were screened. Six quinazoline compounds showed selective inhibition of yeast transformants expressing P. vivax dhfr genes. The 50% inhibitory concentration (IC 50) of these six compounds was determined against field isolates of P. falciparum. Our results suggest that a close relationship between the yeast assay based on expression of P. vivax dhfr genes and the in vitro test using P. falciparum parasites in culture is a promising initial step for drug screening.