Sequences of the Plasmodium falciparum cytoadherence-linked asexual protein 9 implicated in malaria parasite invasion to erythrocytes.
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.
Pinzón
Carlos Giovanni
CG
Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia.
Curtidor
Hernando
H
García
Jeison
J
Vanegas
Magnolia
M
Vizcaíno
Carolina
C
Patarroyo
Manuel A
MA
Patarroyo
Manuel E
ME
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*
D015815:Cell Adhesion Molecules; D008565:Membrane Proteins; D015800:Protozoan Proteins; D037521:Virulence Factors; C407823:clag9 protein, Plasmodium falciparum; D010447:Peptide Hydrolases