Metabolism and life cycle of brucei trypanosomes.

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We had previously found that mannose inhibited the growth of blood form (BF) of Trypanosoma b. gambiense (Tg) in the culture supported with feeder layer cells. It is necessary to develop the cluture system without feeder layer to study the metabolism of BF. The problem was cleared by using 1 : 1 mixture of MEM and L-15 medium containing 10% fetal bovine serum as the complete medium. ADVANTEC GB140 was the best filter to harmest BF in determination of mannose uptake with ^<14>C-mannose to invesigate that mode of action. Though the experiment shouldbe performed in the absence of glucose as competitive transport with mannose had been reported, glucose is an eminent energy source of BF. BF turned inmobile when incubated in glucose-free Earle's BSS at 37ﾟC the restored by addition of sugar or glycerol. Glucose and glycerol had a similar, while mannose less and galactorse no effect. Our result did not accord with the report that T. b. Brucei (Tb) utilize galactose through glycolytic pathway. Glycerol could be energy source for glucose with no influence on mannose uptake. ^<14>C-mannose uptake was inhibited 50% by addition of 2, 500 times higher concentration of glucose than that of hot mannose. If the competitive transport of Tb reported by others was true, equal concentration might be enough for 50% inhibition. Those discrepancies suggest taht Tg, Howerer, is accepted to be subspecies derived from Tb, they might be quite different in physiological features each other. Fructose 1, 6-bisphosphate, the intermediate metabolite in glycolysis, unexpectedly did harm on BF at much lower concentration than mannose did. Procyclic, a different life cycle stage from BF, resisted to such treatment. In electron micrographs degradation in cytoplasm and Glycosome of BF was observed as early as 2 h after addition of mannose.