dUTPase as a platform for antimalarial drug design: structural basis for the selectivity of a class of nucleoside inhibitors.
Pyrimidine metabolism is a major route for therapeutic intervention against malaria. Here we report inhibition and structural studies on the deoxyuridine nucleotidohydrolase from the malaria parasite Plasmodium falciparum (PfdUTPase). We have identified a series of triphenylmethane derivatives of deoxyuridine with antimalarial activity in vitro which inhibit specifically the Plasmodium dUTPase versus the human enzyme. A 2.4 Angstrom crystal structure of PfdUTPase in complex with one of these inhibitors reveals an atypical trimeric enzyme in which the triphenylmethane derivative can be seen to select for PfdUTPase by way of interactions between the trityl group and the side chains of residues Phe46 and Ile117. Immunofluorescence microscopy studies of parasitized red blood cells reveal that enzyme concentrations are highest during the trophozoite/schizont stages, suggesting that PfdUTPase has a major role in DNA replication. Taken together the data show that PfdUTPase may be considered as an antimalarial drug target.
Whittingham
Jean L
JL
Structural Biology Laboratory, Department of Chemistry, University of York, Heslington, York YO10 5YW, United Kingdom.
Leal
Isabel
I
Nguyen
Corinne
C
Kasinathan
Ganasan
G
Bell
Emma
E
Jones
Andrew F
AF
Berry
Colin
C
Benito
Agustin
A
Turkenburg
Johan P
JP
Dodson
Eleanor J
EJ
Ruiz Perez
Luis M
LM
Wilkinson
Anthony J
AJ
Johansson
Nils Gunnar
NG
Brun
Reto
R
Gilbert
Ian H
IH
Gonzalez Pacanowska
Dolores
D
Wilson
Keith S
KS
D000595:Amino Acid Sequence; D000818:Animals; D000962:Antimalarials / Q000737:chemistry* / Q000494:pharmacology*; D003460:Crystallization; D018360:Crystallography, X-Ray; D015195:Drug Design; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology; D006801:Humans; D008969:Molecular Sequence Data; D010963:Plasmodium falciparum / Q000201:enzymology*; D017433:Protein Structure, Secondary; D011755:Pyrophosphatases / Q000037:antagonists & inhibitors* / Q000737:chemistry*; D014320:Triphenylmethyl Compounds / Q000737:chemistry
D000962:Antimalarials; D004791:Enzyme Inhibitors; D014320:Triphenylmethyl Compounds; C046945:triphenylmethane; D011755:Pyrophosphatases; C020020:dUTP pyrophosphatase