Development of microbial sensing strain: an initiative for detecting aromatic hydrocarbon in industrial wastewater

Abstract

Industrialization is increasing with the progressing world. An industry not only synthesizes some useful product but also generates lots of wastewater. This wastewater is send to the CETP where is treated and then effluent is discharged into the normal water bodies. Aromatic hydrocarbon is the major pollutant in this wastewater and contributes to refractory COD. Most of the treated effluent discharged into the water bodies never meet CPCB normal limit. Aromatic hydrocarbon has some toxic effects on human bodies and hence if water contaminated with such toxic pollutant is consumed then it will be harmful so it becomes necessary to investigate its amount in wastewater. Till date to detect the amount of hydrocarbon analytical methods are used but almost all analytical methods are costly and requires skilled technician. Biosensor is a cost effective and simpler biological method which can be used to detect hydrocarbon. Genetically modified whole cell based biosensor involves fusion of regulator, promoter/operator and reporter gene. Most of the whole cell-based biosensor was constructed having luxAB reporter gene which generates same signal for all type of pollutants. Aim of investigation was to use specific FP based reporter gene for specific pollutant detection which will be advantageous as it can generate different bioluminescent signal. An attempt has been made to replace luxAB from pPROBE phn luxAB detecting 3-ring aromatic hydrocarbon and pPROBE luxAB tbuT detecting 1- ring aromatic hydrocarbon with cfp and gfp respectively. This will allow detection and differentiation of different aromatic hydrocarbon. For achieving this, ligand-protein binding study using bioinformatics tool had been conducted and the cloning is carried out. Two-step cloning strategy is applied and pJET1.2 vector had been used as a carrier for reporter gene. Presence of reporter gene in clone is confirmed using colony PCR. This microbial sensing strain can be used in developing biosensor for hydrocarbon