title: Primary structure and expression of the dihydropteroate synthetase gene of Plasmodium falciparum.
abstract: The enzyme dihydropteroate synthetase (DHPS) from Plasmodium falciparum is involved in the mechanism of action of the sulfone/sulfonamide group of drugs. We describe the cloning and sequencing of the gene encoding the P. falciparum DHPS enzyme and show that it is a bifunctional enzyme that includes dihydro-6-hydroxymethylpterin pyrophosphokinase (PPPK) at the N terminus of DHPS. The gene encodes a putative protein of 83 kDa that contains two domains that are homologous with the DHPS and PPPK enzymes of other organisms. The PPPK-DHPS gene is encoded on chromosome 8 and has two introns. An antibody raised to the PPPK region of the protein was found to recognize a 68-kDa protein that is expressed throughout the asexual life cycle of the parasite. We have determined the sequence of the DHPS portion of the gene from sulfadoxine-sensitive and -resistant P. falciparum clones and identified sequence differences that may have a role in sulfone/sulfonamide resistance.
authors.affiliation: Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia.
authors.forename: T
authors.initials: T
authors.lastname: Triglia
authors.forename: A F
authors.initials: AF
authors.lastname: Cowman
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D016054:DNA, Protozoan; D004094:Dihydropteroate Synthase / Q000096:biosynthesis / Q000235:genetics*; D017854:Diphosphotransferases / Q000235:genetics / Q000378:metabolism; D017125:Genes, Protozoan; D008969:Molecular Sequence Data; D010963:Plasmodium falciparum / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D017386:Sequence Homology, Amino Acid
chemical_list: D016054:DNA, Protozoan; D004094:Dihydropteroate Synthase; D017854:Diphosphotransferases; C019684:2-amino-4-hydroxy-6-hydroxymethyldihydropteridine pyrophosphokinase