Investigating the Roles of the C-Terminal Domain of Plasmodium falciparum GyrA

PLoS One. 2015 Nov 13;10(11):e0142313. doi: 10.1371/journal.pone.0142313. eCollection 2015.


Malaria remains as one of the most deadly diseases in developing countries. The Plasmodium causative agents of human malaria such as Plasmodium falciparum possess an organelle, the apicoplast, which is the result of secondary endosymbiosis and retains its own circular DNA. A type II topoisomerase, DNA gyrase, is present in the apicoplast. In prokaryotes this enzyme is a proven, effective target for antibacterial agents, and its discovery in P. falciparum opens up the prospect of exploiting it as a drug target. Basic characterisation of P. falciparum gyrase is important because there are significant sequence differences between it and the prokaryotic enzyme. However, it has proved difficult to obtain soluble protein. Here we have predicted a new domain boundary in P. falciparum GyrA that corresponds to the C-terminal domain of prokaryotic GyrA and successfully purified it in a soluble form. Biochemical analyses revealed many similarities between the C-terminal domains of GyrA from E. coli and P. falciparum, suggesting that despite its considerably larger size, the malarial protein carries out a similar DNA wrapping function. Removal of a unique Asn-rich region in the P. falciparum protein did not result in a significant change, suggesting it is dispensable for DNA wrapping.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • DNA Gyrase / chemistry*
  • DNA Gyrase / metabolism
  • Humans
  • Malaria, Falciparum / parasitology*
  • Models, Molecular
  • Molecular Sequence Data
  • Plasmodium falciparum / chemistry*
  • Plasmodium falciparum / metabolism
  • Protein Structure, Tertiary
  • Protozoan Proteins / chemistry*
  • Protozoan Proteins / metabolism
  • Sequence Alignment


  • Protozoan Proteins
  • DNA Gyrase

Grant support

J.G.H. and S.N. were funded by RIKEN Initiative Research Funding awarded to J.G.H. This work was supported by Platform for Drug Discovery, Informatics, and Structural Life Science funded by the Ministry of Education, Culture, Sports, Science and Technology, Japan. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.