Bioluminescent bioreporter Pseudomonas putida TVA8 as a detector of water pollution. Operational conditions and selectivity of free cells sensor

Conditions influencing bioluminescence output from Pseudomonas putida TVA8 harboring chromosomal tod-luxCDABE fusion were followed. In complex media, cell growth was not influenced by the presence of toluene at 53 mg/L Bioluminescence induction was tested in minimal medium. At 15 degrees C the highest bioluminescence induced with toluene (1.325 mg/L) was reached after 6h. At 25 degrees C the bioluminescence maximum was approximately 20% lower but this was reached after 3.5 h, and at temperatures of 7 degrees C, 28 degrees C, 30 degrees C and 34 degrees C, bioluminescence peaked at <= 60% of the maximum. Time courses of bioluminescence were dependent on cell concentrations. The heights of bioluminescence maxima were proportional to toluene concentration in the range 0-26 mg/L Twenty-three organic pollutants (10(3) x diluted saturated solutions) were tested as bioluminescent inducers. The bioluminescence maximum decreased in the order: ethylbenzene > toluene > phenol > benzene > 4-ethyltoluene > 4-fluorotoluene > cumene > isobutylbenzene > styrene > trichloroethylene > o-, p-xylene > cresol > m-xylene > 2-methylnaphthalene > benzylchloride > naphthalene > salicylic acid > hexachlorobenzene > 2-chloronaphthalene > biphenyl > 2-bromonaphthalene > 1,3,5-triethylbenzene. Bioluminescence was also induced with ethanol and methanol and the presence of these alcohols in concentrations of <= 1% increased bioluminescence of toluene. The induction of bioluminescence from samples of wastewater and groundwater contaminated with BTEX (benzene, toluene, ethylbenzene and xylene) from 0.5 to 120 mg/L was demonstrated. (C) 2010 Elsevier Ltd. All rights reserved.