title: Absence of alpha-ketoglutarate dehydrogenase activity and presence of CO2-fixing activity in Plasmodium falciparum grown in vitro in human erythrocytes.
abstract: Plasmodium falciparum-infected human erythrocytes grown in vitro do not release 14CO2 when incubated in the presence of [1-14C]glutamate, despite the presence of glutamate dehydrogenase, implying the absence of alpha-ketoglutarate dehydrogenase activity and the lack of functional tricarboxylic acid cycle in the human malaria parasite. Cultures incubated with [14C]bicarbonate, however, fix CO2 into acid-stable metabolites; CO2 fixation proceeds linearly for up to two hours after an initial brief lag and may contribute appreciably to the metabolism of the parasite.
mesh_terms: D000818:Animals; D002245:Carbon Dioxide / Q000378:metabolism*; D004372:Ducks; D004912:Erythrocytes / Q000469:parasitology*; D005969:Glutamate Dehydrogenase / Q000378:metabolism; D005971:Glutamates / Q000378:metabolism; D018698:Glutamic Acid; D000882:Haplorhini; D006801:Humans; D007655:Ketoglutarate Dehydrogenase Complex / Q000378:metabolism*; D007656:Ketoglutaric Acids / Q000378:metabolism; D007658:Ketone Oxidoreductases / Q000378:metabolism*; D010961:Plasmodium; D010963:Plasmodium falciparum / Q000201:enzymology / Q000378:metabolism*
chemical_list: D005971:Glutamates; D007656:Ketoglutaric Acids; D002245:Carbon Dioxide; D018698:Glutamic Acid; D007658:Ketone Oxidoreductases; D007655:Ketoglutarate Dehydrogenase Complex; D005969:Glutamate Dehydrogenase