Skip to main content
PMC home page
Journal of Bacteriology logoLink to Journal of Bacteriology
. 1991 Jun;173(12):3680–3687. doi: 10.1128/jb.173.12.3680-3687.1991

Expression of Escherichia coli pabA.

P V Tran 1, B P Nichols 1
PMCID: PMC207995  PMID: 2050628

Abstract

Escherichia coli pabA encodes the glutamine amidotransferase subunit of p-aminobenzoate synthase. p-Aminobenzoate synthase catalyzes the conversion of chorismate and glutamine to 4-amino-4-deoxychorismate, which is then converted to p-aminobenzoate by a 4-amino-4-deoxychorismate lyase. The 5'-terminal segment of pabA was previously shown to be transcribed from two different promoters, one near the pabA coding sequence (P1) and one preceding fic (P2). However, a pabA-lacZ translational fusion was expressed only from the mRNA originating at P1. We have determined that expression of a pabA-lacZ chromosomal fusion is not changed by p-aminobenzoate limitation, growth rate, catabolite repression, overexpression of either p-aminobenzoate synthase subunit, or gene dosage of pabA and pabB. The lack of pabA expression from P2 appears to be the result of a stable secondary structure in the intergenic space preceding pabA that sequesters the pabA ribosome binding site. Disruption of the secondary structure by mutation allowed expression of pabA from P2, as did translation of ribosomes into the fic-pabA intergenic region.

Full text

PDF
3684

Images in this article

3683Image
on p.3683
3684Image
on p.3684

Selected References

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

  1. Arps P. J., Winkler M. E. Structural analysis of the Escherichia coli K-12 hisT operon by using a kanamycin resistance cassette. J Bacteriol. 1987 Mar;169(3):1061–1070. doi: 10.1128/jb.169.3.1061-1070.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bognar A. L., Osborne C., Shane B., Singer S. C., Ferone R. Folylpoly-gamma-glutamate synthetase-dihydrofolate synthetase. Cloning and high expression of the Escherichia coli folC gene and purification and properties of the gene product. J Biol Chem. 1985 May 10;260(9):5625–5630. [PubMed] [Google Scholar]
  3. Breeze A. S., Sims P., Stacey K. A. Trimethoprim-resistant mutants of E. coli K12: preliminary genetic mapping. Genet Res. 1975 Jun;25(3):207–214. doi: 10.1017/s0016672300015640. [DOI] [PubMed] [Google Scholar]
  4. Goncharoff P., Nichols B. P. Nucleotide sequence of Escherichia coli pabB indicates a common evolutionary origin of p-aminobenzoate synthetase and anthranilate synthetase. J Bacteriol. 1984 Jul;159(1):57–62. doi: 10.1128/jb.159.1.57-62.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Huang M., Gibson F. Biosynthesis of 4-aminobenzoate in Escherichia coli. J Bacteriol. 1970 Jun;102(3):767–773. doi: 10.1128/jb.102.3.767-773.1970. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Huang M., Pittard J. Genetic analysis of mutant strains of Escherichia coli requiring p-aminobenzoic acid for growth. J Bacteriol. 1967 Jun;93(6):1938–1942. doi: 10.1128/jb.93.6.1938-1942.1967. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Kaplan J. B., Merkel W. K., Nichols B. P. Evolution of glutamine amidotransferase genes. Nucleotide sequences of the pabA genes from Salmonella typhimurium, Klebsiella aerogenes and Serratia marcescens. J Mol Biol. 1985 Jun 5;183(3):327–340. doi: 10.1016/0022-2836(85)90004-x. [DOI] [PubMed] [Google Scholar]
  8. Kaplan J. B., Nichols B. P. Nucleotide sequence of Escherichia coli pabA and its evolutionary relationship to trp(G)D. J Mol Biol. 1983 Aug 15;168(3):451–468. doi: 10.1016/s0022-2836(83)80295-2. [DOI] [PubMed] [Google Scholar]
  9. Kawamukai M., Matsuda H., Fujii W., Nishida T., Izumoto Y., Himeno M., Utsumi R., Komano T. Cloning of the fic-1 gene involved in cell filamentation induced by cyclic AMP and construction of a delta fic Escherichia coli strain. J Bacteriol. 1988 Sep;170(9):3864–3869. doi: 10.1128/jb.170.9.3864-3869.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Kawamukai M., Matsuda H., Fujii W., Utsumi R., Komano T. Nucleotide sequences of fic and fic-1 genes involved in cell filamentation induced by cyclic AMP in Escherichia coli. J Bacteriol. 1989 Aug;171(8):4525–4529. doi: 10.1128/jb.171.8.4525-4529.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Liu J., Walsh C. T. Peptidyl-prolyl cis-trans-isomerase from Escherichia coli: a periplasmic homolog of cyclophilin that is not inhibited by cyclosporin A. Proc Natl Acad Sci U S A. 1990 Jun;87(11):4028–4032. doi: 10.1073/pnas.87.11.4028. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Nichols B. P., Seibold A. M., Doktor S. Z. para-aminobenzoate synthesis from chorismate occurs in two steps. J Biol Chem. 1989 May 25;264(15):8597–8601. [PubMed] [Google Scholar]
  13. Shine J., Dalgarno L. The 3'-terminal sequence of Escherichia coli 16S ribosomal RNA: complementarity to nonsense triplets and ribosome binding sites. Proc Natl Acad Sci U S A. 1974 Apr;71(4):1342–1346. doi: 10.1073/pnas.71.4.1342. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Tran P. V., Bannor T. A., Doktor S. Z., Nichols B. P. Chromosomal organization and expression of Escherichia coli pabA. J Bacteriol. 1990 Jan;172(1):397–410. doi: 10.1128/jb.172.1.397-410.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. VOGEL H. J., BONNER D. M. Acetylornithinase of Escherichia coli: partial purification and some properties. J Biol Chem. 1956 Jan;218(1):97–106. [PubMed] [Google Scholar]
  16. White B. J., Hochhauser S. J., Cintron N. M., Weiss B. Genetic mapping of xthA, the structural gene for exonuclease III in Escherichia coli K-12. J Bacteriol. 1976 Jun;126(3):1082–1088. doi: 10.1128/jb.126.3.1082-1088.1976. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Ye Q. Z., Liu J., Walsh C. T. p-Aminobenzoate synthesis in Escherichia coli: purification and characterization of PabB as aminodeoxychorismate synthase and enzyme X as aminodeoxychorismate lyase. Proc Natl Acad Sci U S A. 1990 Dec;87(23):9391–9395. doi: 10.1073/pnas.87.23.9391. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Yim J. J., Brown G. M. Characteristics of guanosine triphosphate cyclohydrolase I purified from Escherichia coli. J Biol Chem. 1976 Aug 25;251(16):5087–5094. [PubMed] [Google Scholar]

Articles from Journal of Bacteriology are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES