Skip to main content
PMC home page
Journal of Bacteriology logoLink to Journal of Bacteriology
. 1990 Jul;172(7):3707–3710. doi: 10.1128/jb.172.7.3707-3710.1990

Mutations leading to constitutive expression from the TOL plasmid meta-cleavage pathway operon are located at the C-terminal end of the positive regulator protein XylS.

L M Zhou 1, K N Timmis 1, J L Ramos 1
PMCID: PMC213347  PMID: 2193914

Abstract

The XylS protein is the positive activator of the TOL plasmid meta-cleavage pathway operon for the metabolism of alkylbenzoates in Pseudomonas putida. The regulator stimulates transcription from the TOL meta pathway operon promoter (Pm) when activated by benzoate effectors or in the absence of effectors when overproduced. xylS mutant alleles that encode regulators which constitutively mediate expression from Pm were isolated and characterized. The mutant proteins all exhibit single amino acid substitutions adjacent to putative alpha-helix-turn-alpha-helix domains at their C-terminal ends. The XylS mutant proteins can still be partially activated by the usual and unusual benzoate effectors for the wild-type regulator and when activated stimulate higher levels of transcription from Pm.

Full text

PDF

Selected References

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

  1. Abril M. A., Michan C., Timmis K. N., Ramos J. L. Regulator and enzyme specificities of the TOL plasmid-encoded upper pathway for degradation of aromatic hydrocarbons and expansion of the substrate range of the pathway. J Bacteriol. 1989 Dec;171(12):6782–6790. doi: 10.1128/jb.171.12.6782-6790.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bagdasarian M., Timmis K. N. Host: vector systems for gene cloning in Pseudomonas. Curr Top Microbiol Immunol. 1982;96:47–67. doi: 10.1007/978-3-642-68315-2_4. [DOI] [PubMed] [Google Scholar]
  3. Brunelle A., Schleif R. Determining residue-base interactions between AraC protein and araI DNA. J Mol Biol. 1989 Oct 20;209(4):607–622. doi: 10.1016/0022-2836(89)90598-6. [DOI] [PubMed] [Google Scholar]
  4. Franklin F. C., Bagdasarian M., Bagdasarian M. M., Timmis K. N. Molecular and functional analysis of the TOL plasmid pWWO from Pseudomonas putida and cloning of genes for the entire regulated aromatic ring meta cleavage pathway. Proc Natl Acad Sci U S A. 1981 Dec;78(12):7458–7462. doi: 10.1073/pnas.78.12.7458. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Inouye S., Nakazawa A., Nakazawa T. Expression of the regulatory gene xylS on the TOL plasmid is positively controlled by the xylR gene product. Proc Natl Acad Sci U S A. 1987 Aug;84(15):5182–5186. doi: 10.1073/pnas.84.15.5182. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Inouye S., Nakazawa A., Nakazawa T. Molecular cloning of gene xylS of the TOL plasmid: evidence for positive regulation of the xylDEGF operon by xylS. J Bacteriol. 1981 Nov;148(2):413–418. doi: 10.1128/jb.148.2.413-418.1981. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Mermod N., Ramos J. L., Bairoch A., Timmis K. N. The xylS gene positive regulator of TOL plasmid pWWO: identification, sequence analysis and overproduction leading to constitutive expression of meta cleavage operon. Mol Gen Genet. 1987 May;207(2-3):349–354. doi: 10.1007/BF00331600. [DOI] [PubMed] [Google Scholar]
  8. Merrick M. J., Gibbins J. R. The nucleotide sequence of the nitrogen-regulation gene ntrA of Klebsiella pneumoniae and comparison with conserved features in bacterial RNA polymerase sigma factors. Nucleic Acids Res. 1985 Nov 11;13(21):7607–7620. doi: 10.1093/nar/13.21.7607. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Pabo C. O., Sauer R. T. Protein-DNA recognition. Annu Rev Biochem. 1984;53:293–321. doi: 10.1146/annurev.bi.53.070184.001453. [DOI] [PubMed] [Google Scholar]
  10. Prentki P., Krisch H. M. In vitro insertional mutagenesis with a selectable DNA fragment. Gene. 1984 Sep;29(3):303–313. doi: 10.1016/0378-1119(84)90059-3. [DOI] [PubMed] [Google Scholar]
  11. Raibaud O., Schwartz M. Positive control of transcription initiation in bacteria. Annu Rev Genet. 1984;18:173–206. doi: 10.1146/annurev.ge.18.120184.001133. [DOI] [PubMed] [Google Scholar]
  12. Ramos J. L., Mermod N., Timmis K. N. Regulatory circuits controlling transcription of TOL plasmid operon encoding meta-cleavage pathway for degradation of alkylbenzoates by Pseudomonas. Mol Microbiol. 1987 Nov;1(3):293–300. doi: 10.1111/j.1365-2958.1987.tb01935.x. [DOI] [PubMed] [Google Scholar]
  13. Ramos J. L., Michan C., Rojo F., Dwyer D., Timmis K. Signal-regulator interactions. Genetic analysis of the effector binding site of xylS, the benzoate-activated positive regulator of Pseudomonas TOL plasmid meta-cleavage pathway operon. J Mol Biol. 1990 Jan 20;211(2):373–382. doi: 10.1016/0022-2836(90)90358-S. [DOI] [PubMed] [Google Scholar]
  14. Ramos J. L., Stolz A., Reineke W., Timmis K. N. Altered effector specificities in regulators of gene expression: TOL plasmid xylS mutants and their use to engineer expansion of the range of aromatics degraded by bacteria. Proc Natl Acad Sci U S A. 1986 Nov;83(22):8467–8471. doi: 10.1073/pnas.83.22.8467. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Worsey M. J., Williams P. A. Metabolism of toluene and xylenes by Pseudomonas (putida (arvilla) mt-2: evidence for a new function of the TOL plasmid. J Bacteriol. 1975 Oct;124(1):7–13. doi: 10.1128/jb.124.1.7-13.1975. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Yanisch-Perron C., Vieira J., Messing J. Improved M13 phage cloning vectors and host strains: nucleotide sequences of the M13mp18 and pUC19 vectors. Gene. 1985;33(1):103–119. doi: 10.1016/0378-1119(85)90120-9. [DOI] [PubMed] [Google Scholar]

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

RESOURCES