Fine mapping of Plasmodium falciparum ribosomal phosphoprotein PfP0 revealed sequences with highly specific binding activity to human red blood cells Academic Article

journal

  • Journal of Molecular Medicine

abstract

  • The Plasmodium falciparum P0 ribosomal phosphoprotein (PfP0) was identified for the first time by screening a cDNA expression library of P. falciparum parasites with sera from malaria-immune individuals. Due to its localization on the surface of different parasite life-cycle stages (merozoites and gametocytes) and its recognition by invasion-blocking antibodies, PfP0 has been considered a potential malaria-vaccine component. In this study, 16 20-mer-long synthetic peptides spanning the entire PfP0 sequence were evaluated by means of receptor-ligand assays with human red blood cells (RBCs) in order to determine the role played by these peptides in the invasion process. Four RBC high-activity binding peptides (HABPs), located mostly toward the N-terminal region, were identified: HABP 33898 (1MAKLSKQQKKQMYIEKLSSL 20), HABP 33900 (41ASVRKSLRGKATILMGKNTRY60), HABP 33901 (61IRTALKKNLQAVPQIEKLLPY 80), and HABP 33906 (161LIKQGEKVTASSATLLRKFNY180). The binding pattern of HABPs 33898 and 33906 to enzyme-treated RBCs suggests receptors of protein nature for these two HABPs, one of which could correspond to a common 58-kDa RBC membrane protein, as indicated by results of cross-linking assays. Both HABPs exhibited high content of α-helical features and prevented P. falciparum merozoite invasion to RBCs in vitro by up to 91%. The invasion-blocking ability reported here for these PfP0 HABPs supports their inclusion in immunological studies with the aim of assessing their potential as candidates for a vaccine against P. falciparum malaria. © 2009 Springer-Verlag.

publication date

  • 2010/1/1

keywords

  • Blocking Antibodies
  • Enzymes
  • Erythrocytes
  • Falciparum Malaria
  • Gene Library
  • Human Activities
  • Immune Sera
  • In Vitro Techniques
  • Life Cycle Stages
  • Ligands
  • Malaria
  • Malaria Vaccines
  • Membrane Proteins
  • Merozoites
  • Parasites
  • Peptides
  • Phosphoproteins
  • Plasmodium falciparum
  • Proteins
  • Vaccines
  • ribosomal protein P0

International Standard Serial Number (ISSN)

  • 0946-2716

number of pages

  • 14

start page

  • 61

end page

  • 74