Badaut C. auteur aut IRD Faure G. auteur aut IRD Tuikue Ndam Nicaise auteur aut IRD Bertin Gwladys auteur aut IRD Chaffotte A. auteur aut IRD Khattab A. auteur aut IRD Klinkert M.Q. auteur aut IRD Deloron Philippe auteur aut IRD Bentley G.A. auteur aut IRD text journalArticle eng text/pdf born digital access We have previously identified a number of DBL gamma domains in Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) transcripts obtained from placental parasite isolates, showing that they bind specifically to chondroitin sulfate A (CSA) (Khattab A, Kun J, Deloron P, Kremsner PG, Klinkert MQ. Variants of Plasmodium falciparum erythrocyte membrane protein I expressed by different placental parasites are closely related and adhere to chondroitin sulfate A. J Infect Dis 2001;183:1165-9). Here we give a more detailed physico-chemical and binding characterisation of the soluble, recombinant DBL gamma domain derived from one of these isolates. Results from circular dichroism and limited proteolysis experiments are consistent with the recombinant domain being expressed with the native fold. Specific binding of DBL gamma to placental cryosections was demonstrated by labeling with antibodies raised against the recombinant domain; binding was diminished after treatment of the cryosections with chondroitinase or by blocking with anti-CSA antibody, showing that CSA mediates the interaction. Binding of the DBL gamma domain to purified placental chondroitin sulfate proteoglycan (CSPG) was also studied using surface plasmon resonance techniques, with DBL gamma as analyte and CSPG immobilised on the sensor chip; these quantitative measurements gave an affinity constant in the mu-molar range under the conditions used. The native conformation of the DBL gamma domain is essential for CSPG recognition since binding to the sensor chip is abolished when the protein is irreversibly reduced. As with the placental cryosections, association was significantly reduced after treating the immobilised CSPG with chondroitinase. Together, these results demonstrate specific interaction between the DBL gamma domain and the placental receptor. specialized Plasmodium falciparum erythrocyte membrane protein 1 duffy binding like domain placental malaria receptor binding surface plasmon resonance circular dichroism 052 020 151 1 89-99 2007 0166-6851 https://www.documentation.ird.fr/hor/fdi:010037748 10.1016/j.molbiopara.2006.10.010 0166-6851 [F B010037748] https://www.documentation.ird.fr/hor/fdi:010037748 https://www.documentation.ird.fr/intranet/publi/2007/02/010037748.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2007-03-01 2017-08-23 fdi:010037748 fre