A biosensor for the detection of gas toxicity using a recombinant bioluminescent bacterium

A whole-cell biosensor was developed for the detection of gas toxicity usin g a recombinant bioluminescent Escherichia coli harboring a lac::luxCDABE f usion. Immobilization of the cells within LB agar has been done to maintain the activity of the microorganisms and to detect the toxicity of chemicals through the direct contact with gas. Benzene, known as a representative vo latile organic compound, was chosen as a sample toxic gas to evaluate the p erformance of this biosensor based on the bioluminescent response. This bio sensor showed a dose-dependent response, and was found to be reproducible. The immobilizing matrices of this biosensor were stored at 4 degrees C and were maintained for at least a month without any noticible change in its ac tivity. The optimal temperature for sensing was 37 degrees C. A small size of this sensor kit has been successfully fabricated, and found to be applic able as a disposable and portable biosensor to monitor the atmospheric envi ronment of a workplace in which high concentrations of toxic gases could be discharged. (C) 2000 Elsevier Science S.A. All rights reserved.