Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
50
pubmed:dateCreated
2006-12-12
pubmed:abstractText
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.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
281
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
38150-8
pubmed:dateRevised
2007-12-3
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Biochemical and genetic analysis of methylenetetrahydrofolate reductase in Leishmania metabolism and virulence.
pubmed:affiliation
Department of Molecular Microbiology, Washington University School of Medicine, 660 S. Euclid Avenue, St. Louis, MO 63110, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural