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. 1982 Jul;151(1):274–280. doi: 10.1128/jb.151.1.274-280.1982

Cloning of the ilvA538 gene coding for feedback-hypersensitive threonine deaminase from Escherichia coli K-12.

D H Calhoun, J E Gray
PMCID: PMC220238  PMID: 7045077

Abstract

A variety of experimental results implicate the ilvA gene product, threonine deaminase, as an autoregulatory protein that affects the expression of its own gene and those coding for some related proteins. Some of the most direct evidence comes from the analysis of mutations in the ilvA gene with pleiotropic genetic regulatory effects. The most extensively documented mutation, ilvA538, lowers the expression of and abolishes repression control of the ilvGEDA transcription unit. A pleiotropic effect of the ilvA538 mutation, which may be either incidental or mechanistically related to the loss of repression control, renders threonine deaminase feedback hypersensitive to the inhibition of catalytic activity by the pathway end product, isoleucine. We transferred this mutation to lambda dilv phage and pBR322 derivatives. Direct enzyme assay of the plasmid- and phage-coded ilvA538 gene product in delta ilv hosts confirmed the feedback hypersensitivity of the enzyme product. In conjunction with the ilvG671 (phenotype, ILvG+ Valr; previously designated ilvO671) allele located in cis, high levels of the plasmid and lambda dilv phage-coded mutant enzyme suitable for protein purification were observed. Deletion mapping experiments with lambda dilv phage confirmed that the ilvA538 mutation, and not mutations promoter proximal to ilvD (transcription is from ilvG to ilvA), confer a loss of repression control. These genetic mapping studies indicate, however, that an additional mutation(s) may be present that contributes, at least in part, to the reduced enzyme levels in strains with the ilvA538 mutation.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Abrescia P., Guardiola J., Foresti M., Lamberti A., Iaccarino M. Threonine deaminase: autogenous regulator of the ilv genes in Escherichia coli K-12. Mol Gen Genet. 1979 Mar 27;171(3):261–275. doi: 10.1007/BF00267581. [DOI] [PubMed] [Google Scholar]
  2. Bachmann B. J., Low K. B. Linkage map of Escherichia coli K-12, edition 6. Microbiol Rev. 1980 Mar;44(1):1–56. doi: 10.1128/mr.44.1.1-56.1980. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Baez M., Patin D. W., Calhoun D. H. Deletion mapping of the ilvGOEDAC genes of Escherichia coli K-12. Mol Gen Genet. 1979 Feb 1;169(3):289–297. doi: 10.1007/BF00382275. [DOI] [PubMed] [Google Scholar]
  4. Calhoun D. H., Kuska J. S., Hatfield G. W. Threonine deaminase from Escherichia coli. II. Maturation and physical properties of the enzyme from a mutant altered in its regulation of gene expression. J Biol Chem. 1975 Jan 10;250(1):127–131. [PubMed] [Google Scholar]
  5. Calhoun D. H., Rimerman R. A., Hatfield G. W. Threonine deaminase from Escherichia coli. I. Purification and properties. J Biol Chem. 1973 May 25;248(10):3511–3516. [PubMed] [Google Scholar]
  6. Calhoun D. H. Threonine deaminase from Escherichia coli: feedback-hypersensitive enzyme from a genetic regulatory mutant. J Bacteriol. 1976 Apr;126(1):56–63. doi: 10.1128/jb.126.1.56-63.1976. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. FREUNDLICH M., BURNS R. O., UMBARGER H. E. Control of isoleucine, valine, and leucine biosynthesis. I. Multivalent repression. Proc Natl Acad Sci U S A. 1962 Oct 15;48:1804–1808. doi: 10.1073/pnas.48.10.1804. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Gray J. E., Patin D. W., Calhoun D. H. Identification of the protein products of the rrnC, ilv, rho region of the Escherichia coli K-12 chromosome. Mol Gen Genet. 1981;183(3):428–436. doi: 10.1007/BF00268761. [DOI] [PubMed] [Google Scholar]
  9. Guardiola J., Cervone F., Lamberti A., Levinthal M., Laccarino M. Dual autogenous regulatory role of threonine deaminase in Escherichia coli K-12. Mol Gen Genet. 1978 Feb 7;159(1):27–32. doi: 10.1007/BF00401744. [DOI] [PubMed] [Google Scholar]
  10. Hahn J. E., Calhoun D. H. Suppressors of a genetic regulatory mutation affecting isoleucine-valine biosynthesis in Escherichia coli K-12. J Bacteriol. 1978 Oct;136(1):117–124. doi: 10.1128/jb.136.1.117-124.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Hatfield G. W., Burns R. O. Specific binding of leucyl transfer RNA to an immature form of L-threonine deaminase: its implications in repression. Proc Natl Acad Sci U S A. 1970 Aug;66(4):1027–1035. doi: 10.1073/pnas.66.4.1027. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Kline E. L., Manross D. N., Jr, Warwick M. L. Multivalent regulation of isoleucine-valine transaminase in an Escherichia coli K-12 ilvA deletion strain. J Bacteriol. 1977 May;130(2):951–953. doi: 10.1128/jb.130.2.951-953.1977. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Lawther R. P., Hatfield G. W. Multivalent translational control of transcription termination at attenuator of ilvGEDA operon of Escherichia coli K-12. Proc Natl Acad Sci U S A. 1980 Apr;77(4):1862–1866. doi: 10.1073/pnas.77.4.1862. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Levinthal M., Levinthal M., Williams L. S. The regulation of the ilv ADGE operon: evidence for positive control by threonine deaminase. J Mol Biol. 1976 Apr 15;102(3):453–465. doi: 10.1016/0022-2836(76)90327-2. [DOI] [PubMed] [Google Scholar]
  15. Levinthal M., Williams L. S., Umbarger H. E. Role of threonine deaminase in the regulation of isoleucine and valine biosynthesis. Nat New Biol. 1973 Nov 21;246(151):65–68. doi: 10.1038/newbio246065a0. [DOI] [PubMed] [Google Scholar]
  16. Nargang F. E., Subrahmanyam C. S., Umbarger H. E. Nucleotide sequence of ilvGEDA operon attenuator region of Escherichia coli. Proc Natl Acad Sci U S A. 1980 Apr;77(4):1823–1827. doi: 10.1073/pnas.77.4.1823. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Patin D. W., Calhoun D. H. Mapping of ilvO loci of Escherichia coli K-12 with bacteriophage lambda dilv. J Bacteriol. 1979 Mar;137(3):1234–1242. doi: 10.1128/jb.137.3.1234-1242.1979. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Pledger W. J., Umbarger H. E. Isoleucine and valine metabolism in Escherichia coli. XXII. A pleiotropic mutation affecting induction of isomeroreductase activity. J Bacteriol. 1973 Apr;114(1):195–207. doi: 10.1128/jb.114.1.195-207.1973. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Rosenfeld S. A., Brenchley J. Rapid methods for generalized transduction of Salmonella typhimurium mutants. J Bacteriol. 1979 Apr;138(1):261–263. doi: 10.1128/jb.138.1.261-263.1979. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Wasmuth J. J., Umbarger H. E. Role for free isoleucine of glycyl-leucine in the repression of threonine deaminase in Escherichia coli. J Bacteriol. 1974 Jan;117(1):29–39. doi: 10.1128/jb.117.1.29-39.1974. [DOI] [PMC free article] [PubMed] [Google Scholar]

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