A comprehensive model of purine uptake by the malaria parasite Plasmodium falciparum: identification of four purine transport activities in intraerythrocytic parasites

Quashie, N.B., Dorin-Semblat, D., Bray, P.G., Biagini, G.A., Doerig, C., Ranford-Cartwright, L.C. and De Koning, H.P. (2008) A comprehensive model of purine uptake by the malaria parasite Plasmodium falciparum: identification of four purine transport activities in intraerythrocytic parasites. Biochemical Journal, 411(2), pp. 287-295. (doi:10.1042/BJ20071460)

Full text not currently available from Enlighten.

Abstract

Plasmodium falciparum is incapable of de novo purine biosynthesis, and is absolutely dependent on transporters to salvage purines from the environment. Only one low-affinity adenosine transporter has been characterized to date. In the present study we report a comprehensive study of purine nucleobase and nucleoside transport by intraerythrocytic P. falciparum parasites. Isolated trophozoites expressed (i) a high-affinity hypoxanthine transporter with a secondary capacity for purine nucleosides, (ii) a separate high-affinity transporter for adenine, (iii) a low-affinity adenosine transporter, and (iv) a low-affinity/high-capacity adenine carrier. Hypoxanthine was taken up with 12-fold higher efficiency than adenosine. Using a parasite clone with a disrupted PfNT1 (P. falciparum nucleoside transporter 1) gene we found that the high-affinity hypoxanthine/nucleoside transport activity was completely abolished, whereas the low-affinity adenosine transport activity was unchanged. Adenine transport was increased, presumably to partly compensate for the loss of the high-affinity hypoxanthine transporter. We thus propose a model for purine salvage in P. falciparum, based on the highly efficient uptake of hypoxanthine by PfNT1 and a high capacity for purine nucleoside uptake by a lower affinity carrier

Item Type:Articles
Status:Published
Refereed:Yes
Glasgow Author(s) Enlighten ID:Ranford-Cartwright, Dr Lisa and Quashie, Mr Neils and De Koning, Professor Harry
Authors: Quashie, N.B., Dorin-Semblat, D., Bray, P.G., Biagini, G.A., Doerig, C., Ranford-Cartwright, L.C., and De Koning, H.P.
Subjects:Q Science > QR Microbiology
Q Science > QL Zoology
College/School:College of Medical Veterinary and Life Sciences
College of Medical Veterinary and Life Sciences > Institute of Infection Immunity and Inflammation
Journal Name:Biochemical Journal
Publisher:Portland Press Ltd.
ISSN:0264-6021
ISSN (Online):1470-8728

University Staff: Request a correction | Enlighten Editors: Update this record