A drug-selected Plasmodium falciparum lacking the need for conventional electron transport

Mol Biochem Parasitol. 2008 May;159(1):64-8. doi: 10.1016/j.molbiopara.2008.01.002. Epub 2008 Jan 19.

Abstract

Mitochondrial electron transport is essential for survival in Plasmodium falciparum, making the cytochrome (cyt) bc(1) complex an attractive target for antimalarial drug development. Here we report that P. falciparum cultivated in the presence of a novel cyt bc(1) inhibitor underwent a fundamental transformation in biochemistry to a phenotype lacking a requirement for electron transport through the cyt bc(1) complex. Growth of the drug-selected parasite clone (SB1-A6) is robust in the presence of diverse cyt bc(1) inhibitors, although electron transport is fully inhibited by these same agents. This transformation defies expected molecular-based concepts of drug resistance, has important implications for the study of cyt bc(1) as an antimalarial drug target, and may offer a glimpse into the evolutionary future of Plasmodium.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Acridines* / chemistry
  • Acridines* / pharmacology
  • Animals
  • Antimalarials / pharmacology*
  • Atovaquone / pharmacology
  • Drug Resistance* / genetics
  • Electron Transport Complex III / antagonists & inhibitors*
  • Electron Transport Complex III / genetics
  • Electron Transport Complex III / metabolism
  • Electron Transport*
  • Enzyme Inhibitors / pharmacology
  • Humans
  • Inhibitory Concentration 50
  • Parasitic Sensitivity Tests
  • Plasmodium falciparum / drug effects*
  • Plasmodium falciparum / genetics
  • Plasmodium falciparum / growth & development
  • Plasmodium falciparum / metabolism
  • Selection, Genetic
  • Serial Passage

Substances

  • Acridines
  • Antimalarials
  • Enzyme Inhibitors
  • Electron Transport Complex III
  • Atovaquone