Biochemical and genetic analysis of methylenetetrahydrofolate reductase in Leishmania metabolism and virulence.

Article Details

Citation

Copy to clipboard

Vickers TJ, Orsomando G, de la Garza RD, Scott DA, Kang SO, Hanson AD, Beverley SM

Biochemical and genetic analysis of methylenetetrahydrofolate reductase in Leishmania metabolism and virulence.

J Biol Chem. 2006 Dec 15;281(50):38150-8. Epub 2006 Oct 10.

PubMed ID

17032644 [ View in PubMed

]

Abstract

Methylenetetrahydrofolate reductase (MTHFR; EC 1.5.1.20) is the sole enzyme responsible for generation of 5-methyltetrahydrofolate, which is required for methionine synthesis and provision of methyl groups via S-adenosylmethionine. Genome analysis showed that Leishmania species, unlike Trypanosoma brucei and Trypanosoma cruzi, contain genes encoding MTHFR and two distinct methionine synthases. Leishmania MTHFR differed from those in other eukaryotes by the absence of a C-terminal regulatory domain. L. major MTHFR was expressed in yeast and recombinant enzyme was produced in Escherichia coli. MTHFR was not inhibited by S-adenosylmethionine and, uniquely among folate-metabolizing enzymes, showed dual-cofactor specificity with NADH and NADPH under physiological conditions. MTHFR null mutants (mthfr(-)) lacked 5-methyltetrahydrofolate, the most abundant intracellular folate, and could not utilize exogenous homocysteine for growth. Under conditions of methionine limitation mthfr(-) mutant cells grew poorly, whereas their growth was normal in standard culture media. Neither in vitro MTHFR activity nor the growth of mthfr(-) mutants or MTHFR overexpressors were differentially affected by antifolates known to inhibit parasite growth via targets beyond dihydrofolate reductase and pteridine reductase 1. In a mouse model of infection mthfr(-) mutants showed good infectivity and virulence, indicating that sufficient methionine is available within the parasitophorous vacuole to meet the needs of the parasite.

DrugBank Data that Cites this Article

Drug Targets

Drug	Target	Kind	Organism	Pharmacological Action	Actions
NADH	Dihydrofolate reductase	Protein	Humans	Unknown	Not Available	Details