Identification of vital and dispensable sulfur utilization factors in the Plasmodium apicoplast

PLoS One. 2014 Feb 21;9(2):e89718. doi: 10.1371/journal.pone.0089718. eCollection 2014.

Abstract

Iron-sulfur [Fe-S] clusters are ubiquitous and critical cofactors in diverse biochemical processes. They are assembled by distinct [Fe-S] cluster biosynthesis pathways, typically in organelles of endosymbiotic origin. Apicomplexan parasites, including Plasmodium, the causative agent of malaria, harbor two separate [Fe-S] cluster biosynthesis pathways in the their mitochondrion and apicoplast. In this study, we systematically targeted the five nuclear-encoded sulfur utilization factors (SUF) of the apicoplast [Fe-S] cluster biosynthesis pathway by experimental genetics in the murine malaria model parasite Plasmodium berghei. We show that four SUFs, namely SUFC, D, E, and S are refractory to targeted gene deletion, validating them as potential targets for antimalarial drug development. We achieved targeted deletion of SUFA, which encodes a potential [Fe-S] transfer protein, indicative of a dispensable role during asexual blood stage growth in vivo. Furthermore, no abnormalities were observed during Plasmodium life cycle progression in the insect and mammalian hosts. Fusion of a fluorescent tag to the endogenous P. berghei SUFs demonstrated that all loci were accessible to genetic modification and that all five tagged SUFs localize to the apicoplast. Together, our experimental genetics analysis identifies the key components of the SUF [Fe-S] cluster biosynthesis pathway in the apicoplast of a malarial parasite and shows that absence of SUFC, D, E, or S is incompatible with Plasmodium blood infection in vivo.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apicoplasts / genetics
  • Apicoplasts / metabolism*
  • Biosynthetic Pathways
  • Gene Deletion
  • Genes, Lethal
  • Genes, Protozoan
  • Iron-Sulfur Proteins / metabolism
  • Plasmodium berghei / genetics
  • Plasmodium berghei / metabolism*
  • Protein Transport
  • Protozoan Proteins / genetics
  • Protozoan Proteins / metabolism*

Substances

  • Iron-Sulfur Proteins
  • Protozoan Proteins

Grants and funding

This work was supported by the Max Planck Society and partly by the EVIMalaR network (#34). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.