title: Sequences of the Plasmodium falciparum cytoadherence-linked asexual protein 9 implicated in malaria parasite invasion to erythrocytes.
abstract: In this study, we synthesized the complete sequence of the CLAG-9 protein as 67 20-mer-long non-overlapped peptides and assessed their ability to bind to erythrocytes in receptor-ligand assays. Twenty CLAG-9 peptides were found to have specific high-affinity binding ability to erythrocytes (thereby named as HABPs), with nanomolar dissociation constants. CLAG-9 HABPs interacted with different erythrocyte surface receptors having apparent molecular weights of 85, 63 and 34 kDa. CLAG-9 HABPs binding was also affected by pre-treatment of RBCs with enzymes and inhibited erythrocyte invasion in vitro by up to 72% at 200 microM. These results suggest that some protein fragments of CLAG-9 may be part of the molecular machinery used by malaria parasites to invade erythrocytes, hence supporting their study as possible vaccine candidates.
authors.affiliation: Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia.
authors.forename: Carlos Giovanni
authors.initials: CG
authors.lastname: Pinzón
authors.forename: Hernando
authors.initials: H
authors.lastname: Curtidor
authors.forename: Jeison
authors.initials: J
authors.lastname: García
authors.forename: Magnolia
authors.initials: M
authors.lastname: Vanegas
authors.forename: Carolina
authors.initials: C
authors.lastname: Vizcaíno
authors.forename: Manuel A
authors.initials: MA
authors.lastname: Patarroyo
authors.forename: Manuel E
authors.initials: ME
authors.lastname: Patarroyo
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015815:Cell Adhesion Molecules / Q000235:genetics / Q000378:metabolism*; D004912:Erythrocytes / Q000469:parasitology*; D006801:Humans; D007700:Kinetics; D016778:Malaria, Falciparum / Q000469:parasitology*; D008565:Membrane Proteins / Q000737:chemistry / Q000378:metabolism; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010447:Peptide Hydrolases / Q000378:metabolism; D010963:Plasmodium falciparum / Q000472:pathogenicity*; D011485:Protein Binding; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism*; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D015815:Cell Adhesion Molecules; D008565:Membrane Proteins; D015800:Protozoan Proteins; D037521:Virulence Factors; C407823:clag9 protein, Plasmodium falciparum; D010447:Peptide Hydrolases