The compact conformation of the Plasmodium knowlesi myosin tail interacting protein MTIP in complex with the C-terminal helix of myosin A

Mol Biochem Parasitol. 2013 Aug;190(2):56-9. doi: 10.1016/j.molbiopara.2013.06.004. Epub 2013 Jul 4.

Abstract

The myosin motor of the malaria parasite's invasion machinery moves over actin fibers while it is making critical contacts with the myosin-tail interacting protein (MTIP). Previously, in a "compact" Plasmodium falciparum MTIP•MyoA complex, MTIP domains 2 (D2) and 3 (D3) make contacts with the MyoA helix, and the central helix is kinked, but in an "extended" Plasmodium knowlesi MTIP•MyoA complex only D3 interacts with the MyoA helix, and the central helix is fully extended. Here we report the crystal structure of the compact P. knowlesi MTIP•MyoA complex. It appears that, depending on the pH, P. knowlesi MTIP can adopt either the compact or the extended conformation to interact with MyoA. Only at pH values above ~7.0, can key hydrogen bonds can be formed by the imidazole group of MyoA His810 with an aspartate carboxylate from the hinge of MTIP and a lysine amino group of MyoA simultaneously.

Keywords: D2; D3; GAP; Glideosome; Invasion; MTIP; Malaria; PfalMTIP; PknoMTIP; Plasmodium falciparum MTIP; Plasmodium knowlesi MTIP; TRAP; X-ray structure; domain 2 of MTIP; domain 3 of MTIP; glideosome-associated protein; myosin-tail interacting protein; rmsd; root mean square deviation; thrombospondin-related anonymous protein..

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Crystallography, X-Ray
  • Cytoskeletal Proteins / chemistry*
  • Cytoskeletal Proteins / metabolism
  • Hydrogen-Ion Concentration
  • Models, Molecular
  • Plasmodium knowlesi / chemistry*
  • Plasmodium knowlesi / metabolism
  • Protein Binding
  • Protein Conformation / drug effects

Substances

  • Cytoskeletal Proteins

Associated data

  • PDB/4GGN