1887

Abstract

Changes in cell composition of CBS 14 were monitored during growth of batch cultures with NHCl and glutamate as nitrogen sources. Carbohydrate was synthesized at the expense of lipid in NH -grown cells, whereas in glutamate-grown cells lipid accumulation was predominant. Total biomass and protein concentration were similar in both cultures. Uptake of [U-C], [1-C] and [6-C]glucose, and evolution of CO from these sources, by washed suspensions of cells grown on glutamate revealed the flux of carbon during glucose dissimilation was principally via the Embden-Meyerhof pathway (72%), with 28% being metabolized by the pentose phosphate pathway. Both urea and glutamate, when added to the cell suspensions, significantly stimulated glucose catabolism, with the flux of carbon via the former pathway increasing to about 89% of the total. Phosphofructokinase (PFK) was implicated as the likely controlling enzyme to explain these events.

PFK was only detected in extracts prepared from the yeast grown in a carbon-limited (nitrogen-excess) medium; no activity was detected in extracts of cells grown in nitrogen-limited medium. The presence of a protease in these latter extracts was revealed. PFK was purified 92-fold to a final specific activity (in the presence of 10 m-NH ) of 4·2 units (mg protein) and exhibited one broad band on polyacrylamide gel electrophoresis. The apparent mol. wt () of the enzyme was approx. 700000. The major properties of the enzyme were examined to determine its regulatory role during lipid biosynthesis. Unlike the enzyme from no inhibition was found with 10 m-ATP. ADP was not inhibitory either. NH ions increased activity 11-fold by increasing the affinity of the enzyme for both fructose 6-phosphate and ATP. K ions also stimulated activity but to a lesser extent. Activity was severely inhibited by citrate, isocitrate and -aconitate but this inhibition was dramatically alleviated by NH . Inhibition by citrate was competitive with fructose 6-phosphate in the absence of NH ions. The values for citrate were 1·0 m (with no NH ) and 7·2 m (with 10 m-NH ). Long-chain fatty acyl-CoA esters had no significant inhibitory effect. It is concluded that the interplay between the prevailing intracellular concentrations of NH and citrate is the major determinant of the activity of PFK and thus governs the extent to which glucose is converted either to lipid or carbohydrate.

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1984-12-01
2024-04-25
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References

  1. Abrahams S.L., Younathan E.S. 1971; Modulation of the kinetic properties of phospho- fructokinase by ammonium ions. Journal of Biological Chemistry 246:2464–2467
    [Google Scholar]
  2. Atkinson D.E. 1977 Cellular Energy Metabolism and its Regulation. New York, San Francisco & London: Academic Press;
    [Google Scholar]
  3. Atzpodien W., Bode H. 1970; Purification and regulatory properties of ATP-sensitive phospho- fructokinase from yeast. European Journal of Biochemistry 12:126–132
    [Google Scholar]
  4. Bartrons R., Van Schaftingen E., Vissers S., Hers H.G. 1982; The stimulation of yeast phosphofructokinase by fructose 2,6-bisphosphate. FEBS Letters 143:137–140
    [Google Scholar]
  5. Blinc M., Hočevar B. 1953; Fettanreicherung on Rhodotorula gracilis. Monatshefte für Chemie und verwandte Teile anderer Wissenschaften 84:1127–1131
    [Google Scholar]
  6. Bloxham D.P., Lardy H.A. 1973; Phosphofructokinase. In The Enzymes 8, 3rd edn. pp. 239–278 Edited by Boyer P. D. New York: Academic Press;
    [Google Scholar]
  7. Bomsel J.-L., Pradet A. 1968; Study of adenosine 5'-mono, di and triphosphates in plant tissues. Regulation of the level of nucleotides, in vivo, by adenylate kinase: theoretical and experimental study. Biochimica et biophysica acta 162:230–242
    [Google Scholar]
  8. Botham P.A., Ratledge C. 1979; A biochemical explanation for lipid accumulation in Candida 107 and other oleaginous micro-organisms. Journal of General Microbiology 114:361–375
    [Google Scholar]
  9. Boulton C.A., Ratledge C. 1981; Correlation of lipid accumulation in yeasts with possession of ATP: citrate lyase. Journal of General Microbiology 127:169–176
    [Google Scholar]
  10. Boulton C.A., Ratledge C. 1983a; Use of transition studies in continuous cultures of Lipomyces starkeyi, an oleaginous yeast, to investigate the physiology of lipid accumulation. Journal of General Microbiology 129:2871–2876
    [Google Scholar]
  11. Boulton C.A., Ratledge C. 1983b; Partial purification and some properties of ATP: citrate lyase from the oleaginous yeast Lipomyces starkeyi. Journal of General Microbiology 129:2863–2869
    [Google Scholar]
  12. Bradford M.M. 1976; A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Analytical Biochemistry 72:248–254
    [Google Scholar]
  13. Brady R.J., Chambliss G.H. 1967; The lack of phosphofructokinase activity in several species of Rhodotorula. Biochemical and Biophysical Research Communications 29:898–903
    [Google Scholar]
  14. Davis B.J. 1964; Disc electrophoresis. II. Method and application to human serum proteins. Annals of the New York Academy of Sciences 121:404–427
    [Google Scholar]
  15. Diezel W., Bohme H.-J., Nissler C., Freyer R., Heilmann W., Kopperschläger G., Hofmann E. 1973; A new purification procedure for yeast phosphofructokinase minimizing proteolytic degradation. European Journal of Biochemistry 38:479–488
    [Google Scholar]
  16. Doelle H.W., Hollywood N. 1977; The occurrence and distribution of two phosphofructokinase proteins in the facultative anaerobic family of enterobacteriaceae. FEMS Letters 1:31–34
    [Google Scholar]
  17. Evans C.T., Ratledge C. 1983; Biochemical activities during lipid accumulation in Candida curvata. Lipids 18:630–635
    [Google Scholar]
  18. Evans C.T., Ratledge C. 1984a; Effect of nitrogen source on lipid accumulation in oleaginous yeasts. Journal of General Microbiology 130:1693–1704
    [Google Scholar]
  19. Evans C.T., Ratledge C. 1984b; Influence of nitrogen metabolism on lipid accumulation by Rhodosporidum toruloides CBS 14. Journal of General Microbiology 130:1705–1710
    [Google Scholar]
  20. Evans C.T., Scragg A.H., Ratledge C. 1983; Regulation of citrate efflux from mitochondria of oleaginous and non-oleaginous yeasts by long-chain fatty acyl-CoA esters. European Journal of Biochemistry 132:617–622
    [Google Scholar]
  21. Fraenkel D.C. 1982; Carbohydrate metabolism. In The Molecular Biology of the Yeast Saccharomvces: Metabolism and Gene Expression pp. 1–37 Edited by Strathern J.N., Janes E.W., Broach J.R. New York: Cold Spring Harbor Laboratory;
    [Google Scholar]
  22. Gunja-Smith Z., Patil N.B., Smith E.E. 1977; Two pools of glycogen in Saccharomvces. Journal of Bacteriology 130:818–825
    [Google Scholar]
  23. Habison A., Kubicek C.P., Rohr M. 1983; Partial purification and regulatory properties of phosphofructokinase from Aspergillus niger. Biochemical Journal 209:669–676
    [Google Scholar]
  24. Herbert D., Phipps P.J., Strange R.E. 1971; Chemical analysis of microbial cells. Methods in Microbiology 5B:209–344
    [Google Scholar]
  25. Höfer M., Becker J.-U., Brand K., Deckner H., Betz A. 1969; A study of the enzyme equipment of the yeast Rhodotorula gracilis. FEBS Letters 3:322–324
    [Google Scholar]
  26. Höfer M., Brand K., Deckner H., Becker J.-U. 1971; Importance of the pentose phosphate pathway for D-glucose catabolism in the obligatory aerobic yeast Rhodotorula gracilis. Biochemical Journal 123:855–863
    [Google Scholar]
  27. Holzer H., Betz H., Ebner E. 1975; Intracellular proteinases in micro-organisms. Current Topics in Cellular Regulation 9:103–156
    [Google Scholar]
  28. Hughes D.E., Wimpenny J.W.T., Lloyd D. 1971; The disintegration of micro-organisms. Methods in Microbiology 5B:1–54
    [Google Scholar]
  29. Knowles C.J. 1977; Microbial metabolic regulation by adenine nucleotide pools. Symposia of the Society for General Microbiology 27:241–283
    [Google Scholar]
  30. Kopperschläger G., Bar J., Nissler K., Hofmann E. 1977; Physicochemical parameters and subunit composition of yeast phosphofructokinase. European Journal of Biochemistry 81:317–325
    [Google Scholar]
  31. Lindell T.J., Stellwagen E. 1968; Purification and properties of phosphofructokinase from yeast. Journal of Biological Chemistry 243:907–912
    [Google Scholar]
  32. Lloyd D., Kristensen B., Degn H. 1983; Glycolysis and respiration in yeasts: the effect of ammonium ions studied by mass spectrometry. Journal of General Microbiology 129:2125–2127
    [Google Scholar]
  33. Mavis R.D., Stellwagen E. 1970; The role of cations in yeast phosphofructokinase catalysis. Journal of Biological Chemistry 245:674–680
    [Google Scholar]
  34. Mazon M.J., Gancedo J.M., Gancedo C. 1974; Identification of an unusual phosphofructokinase in the red yeast Rhodotorula glutinis. Biochemical and Biophysical Research Communications 61:1304–1309
    [Google Scholar]
  35. Ratledge C., Botham P.A. 1977; Pathway of glucose metabolism in Candida 107, a lipid-accumulating yeast. Journal of General Microbiology 102:391–395
    [Google Scholar]
  36. Rohr M., Kubicek C.P. 1981; Regulatory aspects of citric acid fermentation by Aspergillus niger. Process Biochemistry 16 (no. 4):34–37(+44)
    [Google Scholar]
  37. Salas M.L., Vinuela E., Salas M., Sols A. 1965; Citrate inhibition of phosphofructokinase and the Pasteur effect. Biochemical and Biophysical Research Communications 19:371–376
    [Google Scholar]
  38. Serrano R., Gancedo J.M., Gancedo C. 1973; Assay of yeast enzymes in situ. A potential tool in regulation studies. European Journal of Biochemistry 34:479–482
    [Google Scholar]
  39. Sols A., Salas M.L. 1966; Phosphofructokinase. Methods in Enzymology 9:436–442
    [Google Scholar]
  40. Sols A., Gancedo C., Delafuente G. 1971; Energy-yielding metabolism in yeasts. In The Yeasts 2 pp. 271–308 Edited by Rose A. H. London: Academic Press;
    [Google Scholar]
  41. Trevelyan W.E., Harrison J.S. 1956; Studies on yeast metabolism. Biochemical Journal 63:23–33
    [Google Scholar]
  42. Uyeda K. 1979; Phosphofructokinase. Advances in Enzymology 48:193–244
    [Google Scholar]
  43. Whitworth D.A., Ratledge C. 1975; An analysis of intermediary metabolism and its control in a fat-synthesizing yeast (Candida 107) growing on glucose or alkanes. Journal of General Microbiology 88:275–288
    [Google Scholar]
  44. Witter B., Debuch H., Steiner M. 1974; Die Lipide von Endomycopsis vernalis bei verschiedener Stickstoflf-Ernahrung. Archives of Microbiology 101:321–335
    [Google Scholar]
  45. Wood H.C., Katz J., Landau B. R. 1963; Estimation of pathways of carbohydrate metabolism. Biochemische Zeitschrift 338:809–847
    [Google Scholar]
  46. Zeidan H.M. 1981; Purification and characterization of phosphofructokinase from Rhodotorula glutinis. Biochemical and Biophysical Research Communications 100:681–687
    [Google Scholar]
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