The regulation of poly--hydroxybutyrate metabolism in during balanced growth and starvation Free

Abstract

Activities of the enzymes which are involved in the poly--hydroxybutyrate (PHB) cycle, in both synthesis and degradation reactions, were assayed in crude extracts of cells containing different amounts of PHB. The enzymes of the PHB cycle, of both the synthesis and the degradation process, were more active in PHB-rich cells than in PHB-poor cells. During 96 h of starvation of cells suspended in phosphate buffer, enzymes of the PHB cycle were more active in PHB-rich cells. There was a peak of activity of hydroxybutyrate dehydrogenase (BOHB-DH), -ketothiolase and thiophorase after 24 h of starvation, due to polymer degradation. During the following hours of starvation there was a decrease in the activity of these enzymes. After 24 h of starvation the activity of acetoacetyl-CoA reductase dropped to a minimum level, because the cells could not synthesize PHB under these conditions. The specific activities of BOHB-DH, -ketothiolase and thiophorase were higher in cells which were grown under low oxygen tension and consequently accumulated high levels of PHB, than in cells grown under high oxygen tension, with a low PHB content. Similarities to the pathway of PHB biosynthesis and degradation and its control in are described.

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1990-07-01
2024-03-28
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References

  1. Dawes E.A. editor 1986; Microbial energy reserve compounds. In Microbial Energetics pp 145–165 Glasgow & London: Blackie;
    [Google Scholar]
  2. Dawes E.A., Senior P.J. 1973; The role and regulation of energy reserve polymers in micro-organisms. Advances in Microbial Physiology 10:136–266
    [Google Scholar]
  3. Horan N.J., Shanmugan P. 1986; Effect of starvation and nutrient depletion on the settling properties of activated sludge. Water Research 20:661–666
    [Google Scholar]
  4. Jackson F.A., Dawes E.A. 1976; Regulation of the tricarboxylic acid cycle and poly-β-hydroxybutyrate metabolism in Azotobacter beijerinckii grown under nitrogen or oxygen limitation. Journal of General Microbiology 97:303–312
    [Google Scholar]
  5. Karr D.B., Waters J.K., Suzuki F., Emerich D.W. 1984; Enzymes of the poly-β-hydroxybutyrate and citric acid cycles of Rhizobium japonicum bacteroids. Plant Physiology 75:1158–1162
    [Google Scholar]
  6. Malmcrona-Friberg K., Tunlid A., Marden P., Kjelleberg S., Odham G. 1986; Chemical changes in cell envelope and poly-β-hydroxybutyrate during short-term starvation of a marine bacterial isolate. Archives of Microbiology 144:340–345
    [Google Scholar]
  7. Matin A. 1979; Selective advantage of a Spirillum sp. in a carbon-limited environment. Accumulation of poly-β-hydroxybutyric acid and its role in starvation. Journal of General Microbiology 112:349–355
    [Google Scholar]
  8. Oeding V., Schlegel H.G. 1973; β-Ketothiolase from Hydrogenomonas eutropha H16 and its significance in the regulation of poly-β-hydroxybutyrate metabolism. Biochemical Journal 134:239–248
    [Google Scholar]
  9. Okon Y. 1985a; Azospirillum as a potential inoculant for agriculture. Trends in Biotechnology 3:223–228
    [Google Scholar]
  10. Okon Y. 1985b; The physiology of Azospirillum in relation to its utilization as inoculum for promoting growth of plants. In Nitrogen Fixation and CO2 Metabolism pp 165–174 Ludden P. W., Burris J. E. Edited by New York: Elsevier;
    [Google Scholar]
  11. Okon Y., Albrecht S.L., Burris R.H. 1976; Carbon and ammonia metabolism of Spirillum lipoferum. . Journal of Bacteriology 128:592–597
    [Google Scholar]
  12. Ritchie G.A.F., Senior P.J., Dawes E.A. 1971; The purification and characterization of acetoacetyl-coenzyme A reductase from Azotobacter beijerinckii. . Biochemical Journal 121:309–316
    [Google Scholar]
  13. Ruhr E.M., Schlegel H.G. 1975; Synthesis of poly-β-hydroxybutyrate in vivo and kinetics of β-keto-thiolase (EC 2.3.1.16) in vitro in Alcaligenes eutrophus H-16. Biochemical Society Transactions 3:1093–1094
    [Google Scholar]
  14. Senior P.J., Dawes E.A. 1971; Poly-β-hydroxybutyrate biosynthesis and the regulation of glucose metabolism in Azotobacter beijerinckii. . Biochemical Journal 125:55–66
    [Google Scholar]
  15. Senior P.J., Dawes E.A. 1973; The regulation of poly-β-hydroxybutyrate metabolism in Azotobacter beijerinckii. . Biochemical Journal 134:225–238
    [Google Scholar]
  16. Senior P.J., Beech G.A., Ritchie G.A.F., Dawes E.A. 1972; The role of oxygen limitation in the formation of poly-β-hydroxy-butyrate during batch and continuous culture of Azotobacter beijerinckii. . Biochemical Journal 128:1193–1201
    [Google Scholar]
  17. Stockdale H., Ribbons D.W., Dawes E.A. 1986; Occurrence of poly-β-hydroxy butyrate in the Azotobacteriaceae. Journal of Bacteriology 95:1798–1803
    [Google Scholar]
  18. Tal S., Okon Y. 1985; Production of the reserve material poly-β-hydroxybutyrate and its function in Azospirillum brasilense Cd. Canadian Journal of Microbiology 31:608–613
    [Google Scholar]
  19. Tal S., Smirnoff P., Okon Y. 1990; Purification and characterization of poly-β-hydroxybutyrate in Azospirillum brasilense. . Journal of General Microbiology 136:645–649
    [Google Scholar]
  20. Ward A.C., Rowley B.I., Dawes E.A. 1977; Effect of oxygen and nitrogen limitation of poly-β-hydroxybutyrate biosynthesis in ammonium grown Azotobacter beijerinckii. . Journal of General Microbiology 102:61–68
    [Google Scholar]
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