1887

Abstract

SUMMARY

Mutants of impaired in the biosynthesis of carbamoyl phosphate were obtained. Genetical, physiological and enzymic studies of these mutants showed the existence in this organism of two independent enzymic systems which catalysed the synthesis of carbamoyl phosphate from HCO , glutamine, ATP and Mg. One system provides carbamoyl phosphate for the arginine pathway, the other plays a similar role for the pyrimidine pathway. Carbamoyl phosphate from one pathway is freely available for the other. The mutations have been mapped in three unlinked loci. Two loci determine the argininespecific carbamoyl phosphate synthesizing system. The third locus corresponds to the pyrimidine-specific system. Mutations in either of the two genes concerned with the arginine pathway lead to a deficiency in the activity of that pathway to synthesize carbamoyl phosphate. Crossing a mutant deficient in one of the two arginine loci with a mutant deficient at the other produces a diploid in which complementation occurs. Also, activity may be partially regained by combining the cell-free extracts of the two single mutants. The physiological significance of the two enzymic systems is established by the study of their regulation. The carbamoyl phosphate synthesizing activity of the arginine pathway was repressed to 10% of its value in minimal medium by addition of excess of arginine to the growth medium. The activity corresponding to the pyrimidine pathway was only slightly repressed by uracil but was subject to feed-back inhibition by uridine-5′-triphosphate. These results are compared with the data available for other micro-organisms.

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/content/journal/micro/10.1099/00221287-40-1-127
1965-07-01
2022-01-22
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References

  1. Beckwith J. R., Pardee A. B., Austrian R., Jacob F. 1962; Coordination of thǝ synthesis of the enzymes in the pyrimidine pathway of E. coli. J. molec. Biol 5:618
    [Google Scholar]
  2. Bishop S. H., Campbell J. W. 1963; Carbamyl phosphate synthesis in the earthworm Lumbricus terrestris. Science 142:1583
    [Google Scholar]
  3. Charles H. P. 1962; Response of Neurospora mutants to carbon dioxide. Nature Lond: 195359
    [Google Scholar]
  4. Cohen P. P. 1962 In The Enzymes Boyer P. D., Lardy H., Myrbäch K. 6477 New York: Academic Press Inc;
    [Google Scholar]
  5. Davis B. D. 1962 Cited in The Bacteria Gunsalus I. C., Stanier R. Y. New York and London: Academic Press;
    [Google Scholar]
  6. Davis R. H. 1962; Consequences of a suppressor gene effective with pyrimidine and proline mutants of Neurospora. Genetics 47:351
    [Google Scholar]
  7. Davis R. H. 1963; Neurospora mutant lacking an arginine specific carbamyl phos-phokinase. Science 142:1652
    [Google Scholar]
  8. Davis R. H., Woodward V. W. 1962; The relationship between gene suppression and aspartate transcarbamylase activity in pyr-3 mutants of Neurospora. Genetics 47:1075
    [Google Scholar]
  9. Gorini L., Kalman S. M. 1963; Control by uracil of carbamyl phosphate synthesis in Escherichia coli. Biochim. biophys. Acta 69:355
    [Google Scholar]
  10. Grisolia S., Harmon P. 1962; Acetyl phosphate utilization with animal and bacterial enzymes. Biochim. biophys. Acta 7:357
    [Google Scholar]
  11. Grisolia S., Amelunxen R., Raijman L. 1963; Acetyl and carbamyl phosphate utilization with aspartate transcarbamylase and carbamate kinase. Biochem. Biophys. Res. Communs 11:75
    [Google Scholar]
  12. Hawthorne D. C., Mortimer R. K. 1960; Chromosome mapping in Saccharomyces : centromere-linked genes. Genetics 45:1085
    [Google Scholar]
  13. Jones M. E. 1963; Carbamyl phosphate. Science 140:1373
    [Google Scholar]
  14. Jones M. E., Spector L., Lipmann F. 1955; Carbamyl phosphate, the carbamyl donor in enzymatic citrulline synthesis. J. Am. chem. Soc 77:819
    [Google Scholar]
  15. Lacroute F. 1964; Un cas de double rétro-contrôle: la chaîne de biosynthèse deuracile chez la levure. C. r. Séanc. Soc. Biol 259:1357
    [Google Scholar]
  16. Lacroute F., Piérard A., Grenson M., Wiame J. M. 1964; La biosynthèse du carbamyl phosphate chez Saccharomyces cerevisiae. Arch. int. Physiol. Biochim 72:687
    [Google Scholar]
  17. Levenberg B. 1962; Role of l-glutamine as donor of carbamyl nitrogen for the enzymatic synthesis of citrulline in Agaricus bisporus. J. biol. Chem 237:2590
    [Google Scholar]
  18. Meister A. 1962 In The Enzymes Boyer P. D., Lardy H., Myrbäch K. 6247 New York and London: Academic Press;
    [Google Scholar]
  19. Miller E. J., Harrison J. S. 1950; Growth inhibition of yeast by uracil, and its reversal by arginine. Nature, Lond 166:1035
    [Google Scholar]
  20. Novick R. P., Maas W. K. 1961; Control by endogenously synthesized arginine of the formation of ornithine transcarbamylase in Escherichia coli. J. Bact 81:236
    [Google Scholar]
  21. Ochoa S., Stern J. R. 1952; Carbohydrate metabolism. Ann. Rev. Biochem. 21:547
    [Google Scholar]
  22. Piérard A., Wiame J. M. 1964; Regulation and mutation affecting a glutamine dependent formation of carbamyl phosphate in Escherichia coli. Biochem. Biophys. Res. Communs 15:76
    [Google Scholar]
  23. Reissig J. L. 1960; Forward and back mutation in the pyr-3 region of Neurospora I. Mutation from arginine dependence to prototrophy. Genet. Res 1:356
    [Google Scholar]
  24. Reissig J. L. 1963; Spectrum of forward mutants in the pyr-3 region of Neurospora. J. gen. Microbiol 30:327
    [Google Scholar]
  25. Roepke R. R. 1946; cited in Tatum, F. L. Induced Biochemical Mutations in Bacteria. Cold Spring Harb. symp. Quant. Biol 11:278
    [Google Scholar]
  26. Somlo M. 1962; La l-lacticodéshydrogénase de la levure aérobie. Comparaison des propriétés de l’enzyme lié et de l’enzyme soluble. Biochim. biophys. Acta 65:333
    [Google Scholar]
  27. Stadtman E. R. 1963Symposium on multiple forms of enzymes and control mechanism II. Enzyme multiplicity and function in the regulation of divergent metabolic pathways. Bact. Rev 27170
    [Google Scholar]
  28. Thorne K. J. I., Jones M. E. 1963; Carbamyl and acetyl phosphokinase activities of Streptococcus faecalis and Escherichia coli. J. biol. Chem 238:2992
    [Google Scholar]
  29. Wiame J. M. 1965; La régulation d’embranchements métaboliques. Colloques Cent. natn. Rech. scient Marseille: Juillet 1963;
    [Google Scholar]
  30. Woodward V. W., Davis R. H. 1963; Coordinate changes in complementation, suppression and enzyme phenotypes of a pyr-3 mutant of Neurospora crassa. Heredity 18:21
    [Google Scholar]
  31. Yashphe J., Gorini L. 1965; Phosphorylation of carbamate in vivo and in vitro. J. biol chem 240:1681
    [Google Scholar]
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