1887

Abstract

A bv. VF39 gene () encoding a γ-aminobutyrate (GABA) aminotransferase was identified, cloned and characterized. This gene is thought to be involved in GABA metabolism via the GABA shunt pathway, a theoretical bypass of the 2-oxoglutarate dehydrogenase complex. Mutants in are still able to grow on GABA as a sole carbon and nitrogen source. 2-Oxoglutarate-dependent GABA aminotransferase activity is absent in these mutants, while pyruvate-dependent activity remains unaffected. This indicates that at least two enzymes with different substrate specifities are involved in the GABA metabolism of bv. VF39. The promoter was cloned into a newly constructed, stable promoter-probe vector pJP2, suitable for the study of transcriptional GUS fusions in free-living bacteria and during symbiosis. Under free-living conditions the promoter is induced by GABA and repressed by succinate. Transcriptional regulation is mediated by GabR in a repressor-like manner. During symbiosis with the pea host plant is induced and highly expressed in the symbiotic zone. Nodules induced by mutants, however, are still effective in nitrogen fixation.

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2002-02-01
2019-10-14
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References

  1. Allaway, D., Lodwig, E., Crompton, L. A., Wood, M., Parsons, R., Wheeler, T. R. & Poole, P. S. ( 2000; ). Identification of alanine dehydrogenase and its role in mixed secretion of ammonium and alanine by pea bacteroids. Mol Microbiol 36, 508-515.[CrossRef]
    [Google Scholar]
  2. Altschul, S. F., Madden, T. L., Schäffer, A. A., Zhang, J., Zhang, Z., Miller, W. & Lipman, D. J. ( 1997; ). Gapped b last and psi-blast: a new generation of protein database search programs. Nucleic Acids Res 25, 3389-3402.[CrossRef]
    [Google Scholar]
  3. Arnold, W. & Pühler, A. ( 1988; ). A family of high-copy-number plasmid vectors with single end-label sites for rapid nucleotide sequencing. Gene 70, 171-179.[CrossRef]
    [Google Scholar]
  4. Ausubel, F. M., Brent, R. & Kingston, R. (editors) (1987). Current Protocols in Molecular Biology. New York: Wiley.
  5. Axelos, M., Bardet, C., Liboz, T., Le Van Thai, A., Curie, C. & Lescure, B. ( 1989; ). The gene family encoding the Arabidopsis thaliana translational elongation factor EF-1α: molecular cloning, characterisation and expression. Mol Gen Genet 219, 106-112.[CrossRef]
    [Google Scholar]
  6. Bartsch, K., von Johnn-Marteville, A. & Schulz, A. ( 1990; ). Molecular analysis of two genes of the Escherichia coli gab cluster: nucleotide sequence of the glutamate:succinic semialdehyde transaminase gene (gabT) and characterization of the succinic semialdehyde dehydrogenase gene (gabD). J Bacteriol 172, 7035-7042.
    [Google Scholar]
  7. Beringer, J. E. ( 1974; ). R factor transfer in Rhizobium leguminosarum. J Gen Microbiol 84, 188-198.[CrossRef]
    [Google Scholar]
  8. Bradford, M. M. ( 1976; ). A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem 72, 248-254.[CrossRef]
    [Google Scholar]
  9. Boesten, B., Batut, J. & Boistard, P. ( 1998; ). DctBD-dependent and -independent expression of the Sinorhizobium (Rhizobium) meliloti C4-dicarboxylate transport gene (dctA) during symbiosis. Mol Plant–Microbe Interact 11, 878-886.[CrossRef]
    [Google Scholar]
  10. Colonna-Romano, S., Arnold, W., Schlüter, A., Boistard, P., Pühler, A. & Priefer, U. B. ( 1990; ). An Fnr-like protein encoded in Rhizobium leguminosarum bv. viciae shows structural and functional homology to Rhizobium meliloti FixK. Mol Gen Genet 223, 138-147.[CrossRef]
    [Google Scholar]
  11. Dombrecht, B., Vanderleyden, J. & Michiels, J. ( 2001; ). Stable RK2-derived cloning vectors for the analysis of gene expression and gene function in gram-negative bacteria. Mol Plant–Microbe Interact 14, 426-430.[CrossRef]
    [Google Scholar]
  12. Dover, S. & Halpern, Y. S. ( 1971; ). Utilisation of γ-aminobutyric acid as sole carbon and nitrogen source by Escherichia coli K-12 mutants. J Bacteriol 109, 835-843.
    [Google Scholar]
  13. Dunn, M. F. ( 1998; ). Tricarboxylic acid cycle and anapleurotic enzymes in Rhizobia. FEMS Microbiol Rev 22, 105-123.[CrossRef]
    [Google Scholar]
  14. Jovanovic, G. & Model, P. ( 1997; ). PspF and IHF bind co-operatively in the psp promoter-regulatory region of Escherichia coli. Mol Microbiol 25, 473-481.[CrossRef]
    [Google Scholar]
  15. Kaneko, T., Nakamura, Y., Sato, S. & 21 other authors ( 2000; ). Complete genome structure of the nitrogen-fixing symbiotic bacterium Mesorhizobium loti (supplement). DNA Res 7, 381–406.[CrossRef]
    [Google Scholar]
  16. Kouchi, H., Fukai, K. & Kihara, A. ( 1991; ). Metabolism of glutamate and aspartate in bacteroids isolated from soybean root nodules. J Gen Microbiol 137, 2901-2910.[CrossRef]
    [Google Scholar]
  17. Maniatis, T., Fritsch, E. F. & Sambrook, J. (1982). Molecular Cloning: a Laboratory Manual. Cold Spring Harbor, NY: Cold Spring Harbor Laboratory.
  18. McDermott, T. R., Griffith, S. M., Vance, C. P. & Graham, P. H. ( 1989; ). Carbon metabolism in Bradyrhizobium japonicum bacteroids. FEMS Microbiol Lett 63, 327-340.
    [Google Scholar]
  19. McRae, D. G., Miller, R. W. & Berndt, W. B. ( 1989; ). Viability of alfalfa nodule bacteroids isolated by density gradient centrifugation. Symbiosis 7, 67-80.
    [Google Scholar]
  20. Miller, R. W., McRae, D. G. & Joy, K. ( 1991; ). Glutamate and gamma-aminobutyrate metabolism in isolated Rhizobium meliloti bacteroids. Mol Plant–Microbe Interact 4, 37-45.[CrossRef]
    [Google Scholar]
  21. Poole, P. S. & Allaway, D. ( 2000; ). Carbon and nitrogen metabolism in Rhizobium. Adv Microb Physiol 43, 117-163.
    [Google Scholar]
  22. Poole, P. S., Blyth, A., Reid, C. J. & Walters, K. ( 1994; ). myo-Inositol catabolism and catabolite regulation in Rhizobium leguminosarum bv. viciae. Microbiology 140, 2787-2795.[CrossRef]
    [Google Scholar]
  23. Priefer, U. B. ( 1989; ). Genes involved in lipopolysaccharide production and symbiosis are clustered on the chromosome of Rhizobium leguminosarum bv. viciae VF39. J Bacteriol 171, 6161-6168.
    [Google Scholar]
  24. Salminen, S. O. & Streeter, J. G. ( 1992; ). Labelling of carbon pools in Bradyrhizobium japonicum and Rhizobium leguminosarum bv. viciae bacteroids following incubation of intact nodules with 14CO2. Plant Physiol 100, 597-604.[CrossRef]
    [Google Scholar]
  25. Schäfer, A., Tauch, A., Jäger, W., Kalinowski, J., Thierbach, G. & Pühler, A. ( 1994; ). Small mobilizable multi-purpose cloning vectors derived from the Escherichia coli plasmids pK18 and pK19: selection of defined deletions in the chromosome of Corynebacterium glutamicum. Gene 145, 69-73.[CrossRef]
    [Google Scholar]
  26. Simon, R., Priefer, U. B. & Pühler, A. ( 1983; ). A broad host range mobilization system for in vivo genetic engineering: transposon mutagenesis in Gram negative bacteria. Bio/Technology 1, 784-791.[CrossRef]
    [Google Scholar]
  27. Simon, R., Quandt, J. & Klipp, W. ( 1989; ). New derivatives of transposon Tn5 suitable for mobilization of replicons, generation of operon fusions and induction of genes in Gram-negative bacteria. Gene 80, 161-169.[CrossRef]
    [Google Scholar]
  28. Stover, C. K., Pham, X. Q., Erwin, A. L. & 23 other authors ( 2000; ). Complete genome sequence of Pseudomonas aeruginosa PAO1, an opportunistic pathogen. Nature 406, 959–964.[CrossRef]
    [Google Scholar]
  29. Streeter, J. G. ( 1991; ). Transport and metabolism of carbon and nitrogen in legume nodules. Adv Bot Res Incorp Adv Plant Pathol 18, 129-187.
    [Google Scholar]
  30. Vance, C. P. & Heichel, G. H. ( 1991; ). Carbon in N2 fixation: limitation or exquisite adaptation. Annu Rev Plant Physiol Plant Mol Biol 42, 373-392.[CrossRef]
    [Google Scholar]
  31. Vincent, J. M. (1970). A Manual for the Practical Study of Root Nodule Bacteria. Oxford: Blackwell Scientific.
  32. Walshaw, D. L., Wilkinson, A., Mundy, M., Smith, M. & Poole, P. S. ( 1997; ). Regulation of the TCA cycle and the general amino acid permease by overflow metabolism in Rhizobium leguminosarum. Microbiology 143, 2209-2221.
    [Google Scholar]
  33. Waters, J. K., Hughes, B. L., Purcell, L. C., Gerhardt, K. O., Mawhinney, T. P. & Emerich, D. W. ( 1998; ). Alanine, not ammonia, is excreted from N2-fixing soybean nodule bacteroids. Proc Natl Acad Sci USA 95, 12038-12042.[CrossRef]
    [Google Scholar]
  34. Weinstein, M., Roberts, R. C. & Helinski, D. R. ( 1992; ). A region of the broad-host-range plasmid RK2 causes stable in planta inheritance of plasmids in Rhizobium meliloti cells isolated from alfalfa root nodules. J Bacteriol 174, 7486-7489.
    [Google Scholar]
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