The Trypanosoma cruzi TcrNT2 nucleoside transporter is a conduit for the uptake of 5-F-2’-deoxyuridine and tubercidin analogues

Aldfer, M. M. , Alfayez, I. A., Elati, H. A.A. , Gayen, N., Elmahallawy, E. K., Murillo, A. M., Marsiccobetre, S., Van Calenbergh, S., Siber, A. M. and De Koning, H. P. (2022) The Trypanosoma cruzi TcrNT2 nucleoside transporter is a conduit for the uptake of 5-F-2’-deoxyuridine and tubercidin analogues. Molecules, 27(22), 8045. (doi: 10.3390/molecules27228045) (PMID:36432150) (PMCID:PMC9693223)

Abstract

Among the scarce validated drug targets against Chagas disease (CD), caused by Trypanosoma cruzi, the parasite’s nucleoside salvage system has recently attracted considerable attention. Although the trypanocidal activity of tubercidin (7-deazapurine) has long been known, the identification of a class of 7-substituted tubercidin analogs with potent in vitro and in vivo activity and much-enhanced selectivity has made nucleoside analogs among the most promising lead compounds against CD. Here, we investigate the recently identified TcrNT2 nucleoside transporter and its potential role in antimetabolite chemotherapy. TcrNT2, expressed in a Leishmania mexicana cell line lacking the NT1 nucleoside transporter locus, displayed very high selectivity and affinity for thymidine with a Km of 0.26 ± 0.05 µM. The selectivity was explained by interactions of 2-oxo, 4-oxo, 5-Me, 3′-hydroxy and 5′-hydroxy with the transporter binding pocket, whereas a hydroxy group at the 2′ position was deleterious to binding. This made 5-halogenated 2′-deoxyuridine analogues good substrates but 5-F-2′-deoxyuridine displayed disappointing activity against T. cruzi trypomastigotes. By comparing the EC50 values of tubercidin and its 7-substituted analogues against L. mexicana Cas9, Cas9ΔNT1 and Cas9ΔNT1+TcrNT2 it was shown that TcrNT2 can take up tubercidin and, at a minimum, a subset of the analogs.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: De Koning, Professor Harry and Aldfer, Mustafa Mohamed and Elati, Hamza Ali Abd and ALFAYEZ, IBRAHIM ABDULLAH M
• Authors: Aldfer, M. M., Alfayez, I. A., Elati, H. A.A., Gayen, N., Elmahallawy, E. K., Murillo, A. M., Marsiccobetre, S., Van Calenbergh, S., Siber, A. M., and De Koning, H. P.
• College/School: College of Medical Veterinary and Life Sciences > School of Infection & Immunity > Centre for Virus Research
• Journal Name: Molecules
• Publisher: MDPI
• ISSN: 1420-3049
• ISSN (Online): 1420-3049
• Copyright Holders: Copyright © 2022 by the authors.
• First Published: First published in Molecules 27(22):8045
• Publisher Policy: Reproduced under a Creative Commons license