title: A key role for old yellow enzyme in the metabolism of drugs by Trypanosoma cruzi.
abstract: Trypanosoma cruzi is the etiological agent of Chagas' disease. So far, first choice anti-chagasic drugs in use have been shown to have undesirable side effects in addition to the emergence of parasite resistance and the lack of prospect for vaccine against T. cruzi infection. Thus, the isolation and characterization of molecules essential in parasite metabolism of the anti-chagasic drugs are fundamental for the development of new strategies for rational drug design and/or the improvement of the current chemotherapy. While searching for a prostaglandin (PG) F(2alpha) synthase homologue, we have identified a novel "old yellow enzyme" from T. cruzi (TcOYE), cloned its cDNA, and overexpressed the recombinant enzyme. Here, we show that TcOYE reduced 9,11-endoperoxide PGH(2) to PGF(2alpha) as well as a variety of trypanocidal drugs. By electron spin resonance experiments, we found that TcOYE specifically catalyzed one-electron reduction of menadione and beta-lapachone to semiquinone-free radicals with concomitant generation of superoxide radical anions, while catalyzing solely the two-electron reduction of nifurtimox and 4-nitroquinoline-N-oxide drugs without free radical production. Interestingly, immunoprecipitation experiments revealed that anti-TcOYE polyclonal antibody abolished major reductase activities of the lysates toward these drugs, identifying TcOYE as a key drug-metabolizing enzyme by which quinone drugs have their mechanism of action.
authors.affiliation: Department of Molecular Behavioral Biology, Osaka Bioscience Institute, Osaka 565-0874, Japan. kubata@obi.or.jp
authors.forename: Bruno Kilunga
authors.initials: BK
authors.lastname: Kubata
authors.forename: Zakayi
authors.initials: Z
authors.lastname: Kabututu
authors.forename: Tomoyoshi
authors.initials: T
authors.lastname: Nozaki
authors.forename: Craig J
authors.initials: CJ
authors.lastname: Munday
authors.forename: Shunichi
authors.initials: S
authors.lastname: Fukuzumi
authors.forename: Kei
authors.initials: K
authors.lastname: Ohkubo
authors.forename: Michael
authors.initials: M
authors.lastname: Lazarus
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Maruyama
authors.forename: Samuel K
authors.initials: SK
authors.lastname: Martin
authors.forename: Michael
authors.initials: M
authors.lastname: Duszenko
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Urade
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000378:metabolism / Q000494:pharmacology; D001241:Aspirin / Q000378:metabolism / Q000494:pharmacology; D001483:Base Sequence; D002384:Catalysis; D016861:Cyclooxygenase Inhibitors / Q000378:metabolism / Q000494:pharmacology; D016054:DNA, Protozoan; D015237:Dinoprost / Q000096:biosynthesis; D015232:Dinoprostone / Q000096:biosynthesis; D015870:Gene Expression; D006911:Hydroxyprostaglandin Dehydrogenases / Q000235:genetics; D007213:Indomethacin / Q000378:metabolism / Q000494:pharmacology; D008969:Molecular Sequence Data; D009252:NADPH Dehydrogenase / Q000235:genetics / Q000378:metabolism*; D009285:Naphthoquinones / Q000378:metabolism; D010084:Oxidation-Reduction; D015230:Prostaglandin D2 / Q000096:biosynthesis; D017386:Sequence Homology, Amino Acid; D014344:Trypanocidal Agents / Q000378:metabolism*; D014349:Trypanosoma cruzi / Q000201:enzymology* / Q000235:genetics
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D016861:Cyclooxygenase Inhibitors; D016054:DNA, Protozoan; D009285:Naphthoquinones; D014344:Trypanocidal Agents; D015237:Dinoprost; D006911:Hydroxyprostaglandin Dehydrogenases; C031051:prostaglandin-F synthase; D009252:NADPH Dehydrogenase; D015232:Dinoprostone; D001241:Aspirin; D015230:Prostaglandin D2; D007213:Indomethacin