Journal of Industrial Microbiology and Biotechnology

, Volume 23, Issue 1, pp 668–676

A single-use luciferase-based mercury biosensor using Escherichia coli HB101 immobilized in a latex copolymer film

  • O K Lyngberg
  • D J Stemke
  • J L Schottel
  • M C Flickinger

DOI: 10.1038/sj.jim.2900679

Cite this article as:
Lyngberg, O., Stemke, D., Schottel, J. et al. J Ind Microbiol Biotech (1999) 23: 668. doi:10.1038/sj.jim.2900679

A single-use Hg(II) patch biosensor has been developed consisting of 1.25-cm diameter patches of two acrylic vinyl acetate copolymer layers coated on polyester. The top layer copolymer was 47 μm thick whereas the bottom layer of copolymer plus E. coli cells was 30 μm thick. The immobilized E. coli HB101 cells harbored a mer-lux plasmid construct and produced a detectable light signal when exposed to Hg(II). The immobilized-cell Hg(II) biosensor had a sensitivity similar to that of suspended cells but a significantly larger detection range. The levels of mercury detected by the patches ranged from 0.1 nM to 10 000 nM HgCl2 in pyruvate buffer, and luciferase induction as a function of Hg(II) concentration was sigmoidal. Luciferase activity was detected in immobilized cells for more than 78 h after exposure of the cells to HgCl2. Addition of 1 mM D-cysteine to the pyruvate buffer increased luciferase induction more than 100-fold in the immobilized cell patches and 3.5-fold in a comparable suspension culture. The copolymer patches with immobilized cells were stable at −20°C for at least 3 months, and the Hg(II)-induced luciferase activity after storage was similar to that of samples assayed immediately after coating. Patches stored desiccated at room temperature for 2 weeks showed lower mercury-induced luciferase activity when compared to freshly prepared patches, but they still had a considerable detection range of 1 to 10 000 nM HgCl2.

Keywords: biosensor; E. coli; immobilization; latex film; luciferase; mercury

Copyright information

© Society for Industrial Microbiology 1999

Authors and Affiliations

  • O K Lyngberg
    • 1
  • D J Stemke
    • 1
  • J L Schottel
    • 2
  • M C Flickinger
    • 1
  1. 1.Biological Process Technology Institute, University of Minnesota, St Paul, MN 55108, USAUS
  2. 2.Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, St Paul, MN 55108, USAUS
  3. 3.Department of Chemical Engineering and Material Science, University of Minnesota, Minneapolis, MN 55454, USAUS