A multi-channel bioluminescent bacterial biosensor for the on-line detection of metals and toxicity. Part I: design and optimization of bioluminescent bacterial strains.
This study describes the construction of inducible bioluminescent strains via genetic engineering along with their characterization and optimization in the detection of heavy metals. Firstly, a preliminary comparative study enabled us to select a suitable carbon substrate from pyruvate, glucose, citrate, diluted Luria-Bertani, and acetate. The latter carbon source provided the best induction ratios for comparison. Results showed that the three constructed inducible strains, Escherichia coli DH1 pBzntlux, pBarslux, and pBcoplux, were usable when conducting a bioassay after a 14-h overnight culture at 30 °C. Utilizing these sensors gave a range of 12 detected heavy metals including several cross-detections. Detection limits for each metal were often close to and sometimes lower than the European standards for water pollution. Finally, in order to maintain sensitive bacteria within the future biosensor-measuring cell, the agarose immobilization matrix was compared to polyvinyl alcohol (PVA). Agarose was selected because the detection limits of the bioluminescent strains were not affected, in contrast to PVA. Specific detection and cross-detection ranges determined in this study will form the basis of a multiple metals detection system by the new multi-channel Lumisens3 biosensor.
Nantes University, PRES UNAM, Campus de la Courtaisière-IUT, UMR CNRS GEPEA, CBAC, La Roche-sur-Yon, France.
Thomas
T
Charrier
Marie-José
MJ
Durand
Sulivan
S
Jouanneau
Michel
M
Dion
Mimma
M
Pernetti
Denis
D
Poncelet
Gérald
G
Thouand
D001419:Bacteria / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D015374:Biosensing Techniques / Q000379:methods*; D002244:Carbon / Q000378:metabolism; D003429:Cross Reactions; D005818:Genetic Engineering / Q000379:methods; D057230:Limit of Detection; D008163:Luminescent Measurements; D008164:Luminescent Proteins / Q000235:genetics; D019216:Metals, Heavy / Q000032:analysis* / Q000633:toxicity; D013045:Species Specificity
D008164:Luminescent Proteins; D019216:Metals, Heavy; D002244:Carbon