Interrelations between Glucose and Alanine Catabolism, Ammonia Production, and the D-Lactate Pathway in Leishmania Braziliensis
L. braziliensis promastigotes catabolize glucose to CO2 and release several incompletely oxidized products. These products, identified by NMR spectroscopy, include succinate, alanine, pyruvate, acetate, and lactate (Darling et al, 1987). Under anaerobic conditions, glycerol becomes a major product and lactate production increases, but glucose consumption decreases (“reverse” Pasteur effect). Enzymatic assays showed that the lactate formed is the D-stereoisomer, and that it is formed via methylglyoxal synthase and glyoxalases I and II (Darling and Blum, submitted for publication). D-lactate dehydrogenase does not appear to be present. The regulation and function of the methylglyoxal pathway in Leishmania are not yet known.
KeywordsLactate Pyruvate Glutamine Alanine Succinate
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