Screening of Bioluminescent Bacterial strains for evolution of Novel Toxicity Sensing Beads

In the present study, exploration of the diverse marine ecosystems of Dapoli beach, Kokan, Maharashtra, India (Asia) for possible isolation of novel bioluminescence bacterial species was undertaken. Further, these isolates were analysed for their potential use as a biological indicators. Preliminary isolation and screening of isolated bioluminescent bacteria was done by morphological & biochemical techniques.  Furthermore, the molecular characterization was accomplished by the 16s rDNA analysis. The 16S rDNA amplified genes was sequenced and sequences were analysed by BLAST for similarity search which confirmed that DM & DS designated isolates were Vibrio fischeri & Photobacterium phosphoreum respectively. Phylogenetic analysis was done with the aid of MEGA 4.0 software. Additionally, the lux genes were also amplified as a bioluminescent bacterial strain specific marker gene.Moreover, the biosensing capability of isolates was investigated against various forms of heavy metals & antibiotics. Correlating luminescence pattern of isolates against toxic pollutants generated during proposed investigations would be of great help to develop an efficient & rapid water pollution monitoring biosensor. Finally, these bacterial strains were immobilized in varied percentage of sodium alginate and concentrations of calcium chloride, respectively. 1% sodium alginate & 0.1M CaCl₂ is found to be most appropriate immobilization material. Bioluminescent beads were tested against various toxic heavy metal compounds. These bioluminescent beads are reusable for atleast two times & would prove to be the secure, rapid, and responsive monitoring system which could detect a wide variety of heavy metal pollutants.