TY - JOUR
T1 - Metabolic studies of the protozoan parasite, Crithidia luciliae, using proton nuclear magnetic resonance spectroscopy
AU - Gilroy, Frances V.
AU - Edwards, Michael R.
AU - Norton, Raymond S.
AU - O'Sullivan, William J.
PY - 1988
Y1 - 1988
N2 - Proton nuclear magnetic resonance (NMR) spectroscopy was used to follow glucose metabolism in Crithidia luciliae. Parasites were grown aerobically and anaerobically in culture, with glucose as the major carbon source and 1H NMR spectra were acquired for the cell free medium. The 1H NMR resonances of metabolites utilised and produced during cell growth were identified by difference spectroscopy, and quantitated from standard curves using 3-trimethylsilyl propionate-2,2,3,3-d4 sodium salt as an internal standard. The major metabolites produced by C. luciliae grown aerobically on 8 mM glucose were succinate, pyruvate, acetate and ethanol, in final concentrations in the media when the cells entered stationary phase of 8.5±0.5, 5.0±0.3, 2.1±0.2 and 2.5±0.6 mM, respectively. The production of succinate and pyruvate, but not acetate and ethanol, followed closely the growth curve of the parasites. Succinate was also measured enzymically and glucose using an autoanalyser. In both cases the results correlated well with the NMR data. The amounts of end products formed were greater than could be accounted for by the utilisation of glucose or any other metabolite observable in the 1H NMR spectra. There was approximately one extra atom of carbon for each molecule of succinate formed, supporting the view that succinate is produced via phosphoenolpyruvate carboxykinase and carbon dioxide fixation. Anaerobically the same major metabolites were produced, but with a decreased ratio of succinate to acetate and ethanol. The formation of glycerol from glucose was not observed under these conditions.
AB - Proton nuclear magnetic resonance (NMR) spectroscopy was used to follow glucose metabolism in Crithidia luciliae. Parasites were grown aerobically and anaerobically in culture, with glucose as the major carbon source and 1H NMR spectra were acquired for the cell free medium. The 1H NMR resonances of metabolites utilised and produced during cell growth were identified by difference spectroscopy, and quantitated from standard curves using 3-trimethylsilyl propionate-2,2,3,3-d4 sodium salt as an internal standard. The major metabolites produced by C. luciliae grown aerobically on 8 mM glucose were succinate, pyruvate, acetate and ethanol, in final concentrations in the media when the cells entered stationary phase of 8.5±0.5, 5.0±0.3, 2.1±0.2 and 2.5±0.6 mM, respectively. The production of succinate and pyruvate, but not acetate and ethanol, followed closely the growth curve of the parasites. Succinate was also measured enzymically and glucose using an autoanalyser. In both cases the results correlated well with the NMR data. The amounts of end products formed were greater than could be accounted for by the utilisation of glucose or any other metabolite observable in the 1H NMR spectra. There was approximately one extra atom of carbon for each molecule of succinate formed, supporting the view that succinate is produced via phosphoenolpyruvate carboxykinase and carbon dioxide fixation. Anaerobically the same major metabolites were produced, but with a decreased ratio of succinate to acetate and ethanol. The formation of glycerol from glucose was not observed under these conditions.
KW - H magnetic resonance spectroscopy
KW - Crithidia luciliae
KW - Glucose metabolism
KW - Kinetoplastida
KW - Succinate
UR - http://www.scopus.com/inward/record.url?scp=0024110072&partnerID=8YFLogxK
U2 - 10.1016/0166-6851(88)90161-2
DO - 10.1016/0166-6851(88)90161-2
M3 - Article
C2 - 2847042
AN - SCOPUS:0024110072
SN - 0166-6851
VL - 31
SP - 107
EP - 115
JO - Molecular and Biochemical Parasitology
JF - Molecular and Biochemical Parasitology
IS - 2
ER -