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. 1989 Mar;171(3):1616–1622. doi: 10.1128/jb.171.3.1616-1622.1989

A protein required for transcriptional regulation of Agrobacterium virulence genes spans the cytoplasmic membrane.

S C Winans 1, R A Kerstetter 1, J E Ward 1, E W Nester 1
PMCID: PMC209789  PMID: 2921246

Abstract

The VirA protein is one of two proteins required for transcriptional activation of Agrobacterium tumefaciens virulence genes in response to phenolic compounds released by plants during infection. We describe two experimental approaches which indicate that this protein has a transmembrane topology. First, spheroplasts of Escherichia coli or wild-type A. tumefaciens expressing the VirA protein were treated with proteinase K to digest periplasmic proteins, and the remaining proteins were immunologically stained on Western blots (immunoblots) by using anti-VirA antibody. Second, transposon TnphoA was used to generate translational fusions between virA and phoA, the latter of which is the structural gene for alkaline phosphatase. Both techniques indicated that VirA spans the cytoplasmic membrane, with approximately 275 amino acids near the amino terminus being localized in the periplasmic space and the rest of the protein being localized in the cytoplasm. We also show that overexpression of VirA in E. coli is deleterious to cell growth and that this phenomenon depends on the synthesis of either the second hydrophobic core or some nearby portion of the VirA protein.

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Selected References

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  1. Akiyama Y., Ito K. Topology analysis of the SecY protein, an integral membrane protein involved in protein export in Escherichia coli. EMBO J. 1987 Nov;6(11):3465–3470. doi: 10.1002/j.1460-2075.1987.tb02670.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Albin R., Weber R., Silverman P. M. The Cpx proteins of Escherichia coli K12. Immunologic detection of the chromosomal cpxA gene product. J Biol Chem. 1986 Apr 5;261(10):4698–4705. [PubMed] [Google Scholar]
  3. Chun S. Y., Parkinson J. S. Bacterial motility: membrane topology of the Escherichia coli MotB protein. Science. 1988 Jan 15;239(4837):276–278. doi: 10.1126/science.2447650. [DOI] [PubMed] [Google Scholar]
  4. Comeau D. E., Ikenaka K., Tsung K. L., Inouye M. Primary characterization of the protein products of the Escherichia coli ompB locus: structure and regulation of synthesis of the OmpR and EnvZ proteins. J Bacteriol. 1985 Nov;164(2):578–584. doi: 10.1128/jb.164.2.578-584.1985. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Gutierrez C., Barondess J., Manoil C., Beckwith J. The use of transposon TnphoA to detect genes for cell envelope proteins subject to a common regulatory stimulus. Analysis of osmotically regulated genes in Escherichia coli. J Mol Biol. 1987 May 20;195(2):289–297. doi: 10.1016/0022-2836(87)90650-4. [DOI] [PubMed] [Google Scholar]
  6. Hess J. F., Oosawa K., Kaplan N., Simon M. I. Phosphorylation of three proteins in the signaling pathway of bacterial chemotaxis. Cell. 1988 Apr 8;53(1):79–87. doi: 10.1016/0092-8674(88)90489-8. [DOI] [PubMed] [Google Scholar]
  7. Hinton J. C., Salmond G. P. Use of TnphoA to enrich for extracellular enzyme mutants of Erwinia carotovora subspecies carotovora. Mol Microbiol. 1987 Nov;1(3):381–386. doi: 10.1111/j.1365-2958.1987.tb01946.x. [DOI] [PubMed] [Google Scholar]
  8. Hurn B. A., Chantler S. M. Production of reagent antibodies. Methods Enzymol. 1980;70(A):104–142. doi: 10.1016/s0076-6879(80)70044-7. [DOI] [PubMed] [Google Scholar]
  9. Kuhn A., Wickner W., Kreil G. The cytoplasmic carboxy terminus of M13 procoat is required for the membrane insertion of its central domain. Nature. 1986 Jul 24;322(6077):335–339. doi: 10.1038/322335a0. [DOI] [PubMed] [Google Scholar]
  10. Kunkel T. A., Roberts J. D., Zakour R. A. Rapid and efficient site-specific mutagenesis without phenotypic selection. Methods Enzymol. 1987;154:367–382. doi: 10.1016/0076-6879(87)54085-x. [DOI] [PubMed] [Google Scholar]
  11. Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
  12. Leroux B., Yanofsky M. F., Winans S. C., Ward J. E., Ziegler S. F., Nester E. W. Characterization of the virA locus of Agrobacterium tumefaciens: a transcriptional regulator and host range determinant. EMBO J. 1987 Apr;6(4):849–856. doi: 10.1002/j.1460-2075.1987.tb04830.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Manoil C., Beckwith J. A genetic approach to analyzing membrane protein topology. Science. 1986 Sep 26;233(4771):1403–1408. doi: 10.1126/science.3529391. [DOI] [PubMed] [Google Scholar]
  14. Manoil C., Beckwith J. TnphoA: a transposon probe for protein export signals. Proc Natl Acad Sci U S A. 1985 Dec;82(23):8129–8133. doi: 10.1073/pnas.82.23.8129. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Murphy G., Kavanagh T. Speeding-up the sequencing of double-stranded DNA. Nucleic Acids Res. 1988 Jun 10;16(11):5198–5198. doi: 10.1093/nar/16.11.5198. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Ninfa A. J., Magasanik B. Covalent modification of the glnG product, NRI, by the glnL product, NRII, regulates the transcription of the glnALG operon in Escherichia coli. Proc Natl Acad Sci U S A. 1986 Aug;83(16):5909–5913. doi: 10.1073/pnas.83.16.5909. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Nixon B. T., Ronson C. W., Ausubel F. M. Two-component regulatory systems responsive to environmental stimuli share strongly conserved domains with the nitrogen assimilation regulatory genes ntrB and ntrC. Proc Natl Acad Sci U S A. 1986 Oct;83(20):7850–7854. doi: 10.1073/pnas.83.20.7850. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Osborn M. J., Gander J. E., Parisi E., Carson J. Mechanism of assembly of the outer membrane of Salmonella typhimurium. Isolation and characterization of cytoplasmic and outer membrane. J Biol Chem. 1972 Jun 25;247(12):3962–3972. [PubMed] [Google Scholar]
  19. Osbourn A. E., Barber C. E., Daniels M. J. Identification of plant-induced genes of the bacterial pathogen Xanthomonas campestris pathovar campestris using a promoter-probe plasmid. EMBO J. 1987 Jan;6(1):23–28. doi: 10.1002/j.1460-2075.1987.tb04713.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Ronson C. W., Nixon B. T., Ausubel F. M. Conserved domains in bacterial regulatory proteins that respond to environmental stimuli. Cell. 1987 Jun 5;49(5):579–581. doi: 10.1016/0092-8674(87)90530-7. [DOI] [PubMed] [Google Scholar]
  21. Stachel S. E., Zambryski P. C. Agrobacterium tumefaciens and the susceptible plant cell: a novel adaptation of extracellular recognition and DNA conjugation. Cell. 1986 Oct 24;47(2):155–157. doi: 10.1016/0092-8674(86)90437-x. [DOI] [PubMed] [Google Scholar]
  22. Stachel S. E., Zambryski P. C. virA and virG control the plant-induced activation of the T-DNA transfer process of A. tumefaciens. Cell. 1986 Aug 1;46(3):325–333. doi: 10.1016/0092-8674(86)90653-7. [DOI] [PubMed] [Google Scholar]
  23. Taylor R. K., Miller V. L., Furlong D. B., Mekalanos J. J. Use of phoA gene fusions to identify a pilus colonization factor coordinately regulated with cholera toxin. Proc Natl Acad Sci U S A. 1987 May;84(9):2833–2837. doi: 10.1073/pnas.84.9.2833. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Wickner W. T., Lodish H. F. Multiple mechanisms of protein insertion into and across membranes. Science. 1985 Oct 25;230(4724):400–407. doi: 10.1126/science.4048938. [DOI] [PubMed] [Google Scholar]
  25. Winans S. C., Ebert P. R., Stachel S. E., Gordon M. P., Nester E. W. A gene essential for Agrobacterium virulence is homologous to a family of positive regulatory loci. Proc Natl Acad Sci U S A. 1986 Nov;83(21):8278–8282. doi: 10.1073/pnas.83.21.8278. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Winans S. C., Kerstetter R. A., Nester E. W. Transcriptional regulation of the virA and virG genes of Agrobacterium tumefaciens. J Bacteriol. 1988 Sep;170(9):4047–4054. doi: 10.1128/jb.170.9.4047-4054.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]

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