Construction and Evaluation of a Metal Ion Biosensor
Abstract
E. coli, genetically engineered with a mercury(II)-sensitive promoter and the lux genes from Vibrio fischeri, were used as microbial sensors for the detection of mercury. Evaluation of this genetic construction was carried out by determining the effects of various parameters on cell suspensions maintained at constant conditions in a small vessel. The strongest fight intensities and quickest induction times occurred with cells in the mid-exponential growth phase maintained at 280C, concentrated to 1x10 to the 9th power cells/mL, mixed at very fast speeds, and aerated at 2 vvm (volume of air per volume of culture per minute) during light measurement in the small vessel. The sensitivity of these cells to the mercuric ion lied in the range of 0.02-4 micrometer (4-800 ppb) and the total response time was on the order of one hour, depending on the above parameters. The cells exhibited great specificity for mercury. The cells have almost equal specificity for organic and inorganic form of the. mercuric ion and responded more weakly to the mercurous ion. A simple, inexpensive, durable miniature probe was constructed and operated using the optimum parameters found in the small vessel as a guide. The range of sensitivity to the mercuric ion detected in the probe was 0.01-4 micrometer when aeration was provided....Metal ion biosensor, Bioluminescence, Mer-lux genetic construction, Mercury.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 15, 1993
- Accession Number
- ADA259775
Entities
People
- Georges Belfort
- Lia Tescione
Organizations
- Rensselaer Polytechnic Institute