1887

Abstract

Cell-free extracts from NCIMB 11764 catalysed the degradation of cyanide into products that included CO. formic acid, formamide and ammonia. Cyanide-degrading activity (CDA) was localized to cytosolic cell fractions and was observed at substrate concentrations as high as 100 mM (2600 mg CN I ). At least two different CDAs could be distinguished by: (i) the determination of reaction product stoichiometries, (ii) requirements for NADH and oxygen, and (iii) kinetic analysis. The first activity produced CO and NH as reaction products, was dependent on oxygen and NADH for activity, and displayed an apparent for cyanide of 1·2 mM. The second activity generated formic acid (and NH) plus formamide as reaction products, was oxygen independent, and had an apparent of 12 mM for cyanide. The first enzymic activity was identified as cyanide oxygenase as previously described [Harris, R. E. & Knowles, C. J. (1983) 20, 337-341] whereas the second activity is believed to consist of two enzymes, a cyanide nitrilase (dihydratase) and hydratase (EC4·2.1·66). In addition to these enzymes, cyanide-grown cells were also induced for formate dehydrogenase (EC 1·2.1·2) thereby providing a means of recycling NADH utilized by cyanide oxygenase. A mutant strain having lost the ability to grow on cyanide as a nitrogen source was isolated and shown to be defective in cyanide oxygenase, but not the cyanide nitrilase/hydratase enzymes. This finding together with results showing that the substrate affinity of cyanide oxygenase was tenfold greater than for the nitrilase/hydratase enzymes, indicates that it is this enzyme that is most important in cyanide assimilation. A cyanate-defective mutant was also isolated and shown to be unaffected in cyanide assimilation, indicating that the metabolism of these two compounds is physiologically distinct.

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1994-07-01
2024-12-10
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References

  1. Dorr P.K., Knowles C. J. 1989; Cyanide oxygenase and cyanase activities of Pseudomonasfluorescens NCIMB 1 1764. FEMS Microbiol Left 60:289–294
    [Google Scholar]
  2. Fallon R. D., Cooper D. A., Speece R., Henson M. 1991; Anaerobic biodegradation of cyanide under methanogenic conditions. Appl Environ Microbiol 57:1656–1662
    [Google Scholar]
  3. Fawcett J.K., Scott J. E. 1960; A rapid and precise method for the determination of urea. J Clin Patbol 13:156–159
    [Google Scholar]
  4. Ferry J.G. 1990; Formate dehydrogenase. FEMS Microbiol Rev 87:377–382
    [Google Scholar]
  5. Fry W.E., Millar R. L. 1972; Cyanide degradation by an enzyme from Stemphyliumloti . Arch Biochem Biopbys 151:468–474
    [Google Scholar]
  6. Fry W.E., Evans P. H. 1977; Association of formamide hydrolyase with fungal pathogenicity to cyanogenic plants. Phytopathology 67:1001–1006
    [Google Scholar]
  7. Fry W.E., Myers D. F. 1981; Hydrogen cyanide metabolism by fungal pathogens of cyanogenic plants. In Cyanide in Biology pp. 321–334 Edited by Vennesland B., Conn E. E., Knowles C. J. , Westelv J., Wissing F. . London: Academic Press;
    [Google Scholar]
  8. Harris R., Knowles C. J. 1983a; Isolation and growth of a Pseudomonas species that utilizes cyanide as a source of nitrogen. J Gen Microbiol 129:1005–1011
    [Google Scholar]
  9. Harris R.E., Knowles C. J. 1983b; The conversion of cyanide to ammonia by extracts of a strain of Pseudomonas fluorescens that utilizes cyanide as a source of nitrogen for growth. FEMS Microbiol Lett 20:337–341
    [Google Scholar]
  10. Hopner T., Knappe J. 1974; Formate: determination with formate dehydrogenase. Methods of Enzymatic Analysis 3 pp. 1551–1555 Edited by Bergmeyer H.U. New York: Academic Press;
    [Google Scholar]
  11. Ingvorsen K., Hojer-Pederson B., Godtfredsen S. E. 1991; Novel cyanide-hydrolyzing enzyme from Alcaligenes subsp. denitriflcans . Appl Environ Microbiol 57:1783–1789
    [Google Scholar]
  12. Knowles C.J. 1976; Microorganisms and cyanide. Bacteriol Rev 40:652–680
    [Google Scholar]
  13. Knowles C.J. 1988; Cyanide utilization and degradation by microorganisms. C1BA Found Symp 140:3–15
    [Google Scholar]
  14. Knowles C.J., Bunch A. W. 1986; Microbial cyanide metabolism. Adv Microb Physiol 21:73–111
    [Google Scholar]
  15. Kunz D.A., Nagappan O. 1989; Cyanase-mediated utilization of cyanate in Pseudomonas fluorescens NCIMB 1 1764. Appl Environ Microbiol 55:256–258
    [Google Scholar]
  16. Kunz D. A., Nagappan O., Silva-Avalos J., Delong G. T. 1992; Utilization of cyanide as a nitrogenous substrate by Pseudomonas fluorescens NCIMB 1 1764: evidence for multiple pathways of metabolic conversion. Appl Environ Microbiol 58:2022–2029
    [Google Scholar]
  17. Lambert J. L., Ramasamy J., Paukstells J. V. 1975; Stable reagents for the colorimetric determination of cyanide by modified Konig reactions. Anal Chem 47:916–918
    [Google Scholar]
  18. Meyers P. R., Rawlings D. E., Woods D. R., Lindsey G. G. 1993; Isolation and characterization of a cyanide dihydratase from Bacilluspumilus Cl. J Bacteriol 175:6105–6112
    [Google Scholar]
  19. Nagappan O. 1992 Mechanisms of cyanide assimilation in Pseudomonas fluorescens NCIMB 1 1764. USA: PhD thesis, University of North Texas;
    [Google Scholar]
  20. Neidhardt F. C., Ingraham J. L., Schaechter M. 1990 Physiology of the Bacterial Cell: a Molecular Approach. Sunderland, Massachusetts: Sinauer Associates;
    [Google Scholar]
  21. Pocker Y., Bjorkquist D. W. 1977; Stopped-flow studies of carbon dioxide hydration and bicarbonate dehydration in H20 and DaO. Acid-base and metal ion catalysis. J Am Chem Soc 99:6537–6543
    [Google Scholar]
  22. Quayle J.R. 1966; Formate dehydrogenase. Methods Enyymol 9:360–364
    [Google Scholar]
  23. Rollinson G., Jones R., Meadows M. P., Harris R. E., Knowles C. J. 1987; The growth of a cyanide-utilising strain of Pseudomonas fluorescens in liquid culture on nickel cyanide as a source of nitrogen. FEMS Microbiol Lett 40:199–205
    [Google Scholar]
  24. Silva-Avalos J., Richmond M. G., Nagappan O., Kunz D. A. 1990; Degradation of the metal-cyano complex tetracyanonickel-ate (II) by cyanide-utilizing bacterial isolates. Appl Environ Microbiol 56:3664–3670
    [Google Scholar]
  25. Solomonson L.P. 1981; Cyanide as a metabolic inhibitor. In Cyanide in Biology pp. 11–28 Edited by Vennesland B., Conn E. E. , Knowles C. J. , Westley J., Wissing F. . London: Academic Press;
    [Google Scholar]
  26. Tyler B. 1978; Regulation of the assimilation of nitrogen compounds. Annu Rev Biochem 47:1127–1162
    [Google Scholar]
  27. White J. M., Jones D. D., Huang D., Gauthier J. J. 1988; Conversion of cyanide to formate and ammonia by a pseudomonad obtained from industrial wastewater. J bid Microbiol 3:263–272
    [Google Scholar]
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