Identification of Plasmodium falciparum reticulocyte binding protein RBP-2 homologue a and b (PfRBP-2-Ha and -Hb) sequences that specifically bind to erythrocytes.
Plasmodium falciparum reticulocyte binding protein RBP-2 homologues a and b (PfRBP-2-Ha and -Hb) have been described as being high molecular weight proteins, expressed at the P. falciparum merozoite apical extreme, belonging to a family of proteins found in other Plasmodium involved in the search for erythrocyte populations before being invaded by merozoites. 185, 20-mer-long non-overlapping peptides, spanning the entire PfRBP-2-Ha and -Hb sequences, were synthesised, radiolabelled and tested in erythrocyte binding assays. Fifteen PfRBP-2-Ha and -Hb high binding activity peptides (HBAPs) specifically binding to erythrocytes with high affinity were identified. Dissociation constants were between 70 and 300 nM and Hill coefficients were 1 approximately. HBAPs residues critical for binding to erythrocytes were determined. Cross-linking was performed allowing possible receptors for PfRBP-2-Ha and -Hb to be identified on the surface of the erythrocytes. Some of the HABPs showed merozoite invasion inhibition greater than 90% in in vitro assays.
Ocampo
Marisol
M
Fundación Instituto de Inmunología de Colombia and Universidad Nacional de Colombia, Cra 50 # 26-00 Bogotá, Colombia.
Vera
Ricardo
R
Rodríguez
Luis Eduardo
LE
Curtidor
Hernando
H
Suárez
Jorge
J
García
Javier
J
Puentes
Alvaro
A
López
Ramsés
R
Valbuena
John
J
Tovar
Diana
D
Reyes
Claudia
C
Vega
Sandra
S
Patarroyo
Manuel Elkin
ME
D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D001667:Binding, Competitive; D004912:Erythrocytes / Q000378:metabolism*; D006801:Humans; D008565:Membrane Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism; D010963:Plasmodium falciparum / Q000254:growth & development / Q000378:metabolism / Q000472:pathogenicity*; D011485:Protein Binding; D015800:Protozoan Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D012156:Reticulocytes / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid
D008565:Membrane Proteins; D010455:Peptides; D015800:Protozoan Proteins