Plant Cell Reports

, Volume 21, Issue 10, pp 1020–1026 | Cite as

Expression of the B subunit of Escherichia coli heat-labile enterotoxin as a fusion protein in transgenic tomato

  • A. M. WalmsleyEmail author
  • M. L. Alvarez
  • Y. Jin
  • D. D. Kirk
  • S. M. Lee
  • J. Pinkhasov
  • M. M. Rigano
  • C. J. Arntzen
  • H. S. Mason
Genetic Transformation and Hybridization


Epitopes often require co-delivery with an adjuvant or targeting protein to enable recognition by the immune system. This paper reports the ability of transgenic tomato plants to express a fusion protein consisting of the B subunit of the Escherichia coli heat-labile enterotoxin (LTB) and an immunocontraceptive epitope. The fusion protein was found to assemble into pentamers, as evidenced by its ability to bind to gangliosides, and had an average expression level of 37.8 μg g−1 in freeze-dried transgenic tissues. Processing of selected transgenic fruit resulted in a 16-fold increase in concentration of the antigen with minimal loss in detectable antigen. The species-specific nature of this epitope was shown by the inability of antibodies raised against non-target species to detect the LTB fusion protein. The immunocontraceptive ability of this vaccine will be tested in future pilot mice studies.


Heat labile toxin Fusion protein Immunocontraceptive Tomato Transgenic plants 



Dry weight


Enzyme-linked immunosorbant assay


Entertoxigenic Escherichia coli


Fresh weight


B subunit of Escherichia coli heat-labile enterotoxin


Zona pellucida glycoprotein 3



For valuable technical assistance, the investigators would like to thank Que Quiang, Tracey Cranston and Joan Lenz. This work was supported by the Co-operative Research Centre for Conservation and Management of Marsupials, Axis Genetics, and Dow AgroSciences LLC.


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Copyright information

© Springer-Verlag 2003

Authors and Affiliations

  • A. M. Walmsley
    • 1
    • 2
    Email author
  • M. L. Alvarez
    • 2
  • Y. Jin
    • 2
  • D. D. Kirk
    • 1
  • S. M. Lee
    • 3
  • J. Pinkhasov
    • 2
  • M. M. Rigano
    • 2
  • C. J. Arntzen
    • 2
  • H. S. Mason
    • 1
  1. 1.Boyce Thompson Institute for Plant ResearchCornell UniversityIthacaUSA
  2. 2.Department of Plant BiologyArizona State UniversityTempeUSA
  3. 3.Department of Primary IndustriesQueensland Agricultural Biotechnology CentreBrisbaneAustralia

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