1887

Abstract

The properties of the tryptophanase constitutive mutation have been investigated. It has previously been reported that mutants carrying grow poorly on medium that selects for constitutive expression of tryptophanase. Our results now show that this poor growth can be explained by the inability of tryptophanase to catalyse the synthesis of L-tryptophan from indole, pyruvate and ammonia at a rate sufficient to allow normal growth. Improved media for the characterization of tryptophanase constitutive mutants are described. The mutation rendered tryptophanase synthesis constitutive (at a differential rate that at 37 C is 30% of the fully induced wild-type) and not further inducible. Diploid studies showed that is cis-dominant, but no evidence was found for any effect in . In addition to rendering tryptophanase synthesis constitutive, affects the response of tryptophanase synthesis to different growth temperatures.

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/content/journal/micro/10.1099/00221287-130-6-1535
1984-06-01
2024-05-01
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References

  1. Borck K., Beggs J. D., Brammar W. J., Hopkins A. S., Murray N. E. 1976; The construction in vitro of transducing derivatives of phage lambda. Molecular and General Genetics 146:199–207
    [Google Scholar]
  2. Colome J., Wilcox G., Englesberg E. 1977; Constitutive mutations in the controlling site region of the araBAD operon of Escherichia coli B/r that decrease sensitivity to catabolite repression. Journal of Bacteriology 129:948–958
    [Google Scholar]
  3. Deeley M. C., Yanofsky C. 1981; Nucleotide sequence of the structural gene for tryptophanase of Escherichia coli K-12. Journal of Bacteriology 147:787–796
    [Google Scholar]
  4. Deeley M. C., Yanofsky C. 1982; Transcription initiation at the tryptophanase promoter of Escherichia coli K-12. Journal of Bacteriology 151:942–951
    [Google Scholar]
  5. Edwards R. M., Yudkin M. D. 1982; Location of the gene for the low-affinity tryptophan-specific permease of Escherichia coli. Biochemical Journal 204:617–619
    [Google Scholar]
  6. Katz L., Englesberg E. 1971; Hyperinducibility as a result of mutation in structural genes and self- catabolite repression in the ara operon. Journal of Bacteriology 107:34–52
    [Google Scholar]
  7. Mcfall E., Mandelstam J. 1963; Specific metabolic repression of three induced enzymes in Escherichia coli. Biochemical Journal 89:391–397
    [Google Scholar]
  8. Peck R. M., Markey F., Yudkin M. D. 1971; Effect of 5-fluorouracil on β-galactosidase synthesis in an Escherichia coli mutant resistant to catabolite repression of the lac operon. FEBS tetters 16:43–44
    [Google Scholar]
  9. Sato T., Aida K., Uemura T. 1969; Contribution of glycolysis to catabolite repression of l-tryptophan- ase synthesis in Escherichia coli. Journal of General and Applied Microbiology 15:109–121
    [Google Scholar]
  10. Snell E. E. 1975; Tryptophanase: structure, cataly-tic activities, and mechanism of action. Advances in Enzymology 42:287–333
    [Google Scholar]
  11. Taylor H. V., Yudkin M. D. 1978; Synthesis of tryptophanase in Escherichia coli: isolation and characterization of a structural gene mutant and two regulatory mutants. Molecular and General Genetics 165:95–102
    [Google Scholar]
  12. Vogel H. J., Bonner D. M. 1956; Acetylomithin- ase of Escherichia coli: partial purification and some properties. Journal of Biological Chemistry 218:97–106
    [Google Scholar]
  13. Ward D. F., Yudkin M. D. 1976; Mutations in Escherichia coli that relieve catabolite repression of tryptophanase synthesis. Tryptophanase promoterlike mutations. Journal of General Microbiology 92:133–137
    [Google Scholar]
  14. White M. K., Yudkin M. D. 1979; Complementation analysis of eleven tryptophanase mutations in Escherichia coli. Journal of General Microbiology 114:471–475
    [Google Scholar]
  15. Yudkin M. D. 1976; Mutations in Escherichia coli that relieve catabolite repression of tryptophanase synthesis. Mutations distant from the tryptophanase gene. Journal of General Microbiology 92:125–132
    [Google Scholar]
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