A GFP-based bacterial biosensor with chromosomally integrated sensing cassette for quantitative detection of Hg(II) in environment.
A mercury biosensor was constructed by integrating biosensor genetic elements into E. coli JM109 chromosome in a single copy number, using the attP/attB recombination mechanism of lambda phage. The genetic elements used include a regulatory protein gene (merR) along with operator/promoter (O/P) derived from the mercury resistance operon from pDU1358 plasmid of Serratia marcescens. The expression of reporter gene gfp is also controlled by merR/O/P. Integration of the construct into the chromosome was done to increase the stability and precision of the biosensor. This biosensor could detect Hg(II) ions in the concentration range of 100-1700 nmol/L, and manifest the result as the expression of GFP. The GFP expression was significantly different (P < or = 0.05) for each concentration of inducing Hg(II) ions in the detection range, which reduces the chances of misinterpretation of results. A model using regression method was also derived for the quantification of the concentration of Hg(II) in water samples.
College of Fisheries (CAU), Lembucherra, Tripura 799210, India.
Himanshu
H
Priyadarshi
Absar
A
Alam
P
P
Gireesh-Babu
Rekha
R
Das
Pankaj
P
Kishore
Shivendra
S
Kumar
Aparna
A
Chaudhari
D015374:Biosensing Techniques / Q000379:methods*; D002876:Chromosomes, Bacterial / Q000378:metabolism*; D015169:Colony Count, Microbial; D004783:Environmental Microbiology; D004926:Escherichia coli / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D005453:Fluorescence; D005822:Genetic Vectors / Q000235:genetics; D016680:Genome, Bacterial / Q000235:genetics; D049452:Green Fluorescent Proteins / Q000378:metabolism*; D007477:Ions; D008628:Mercury / Q000032:analysis*; D008954:Models, Biological; D016254:Mutagenesis, Insertional / Q000235:genetics*; D015203:Reproducibility of Results
D007477:Ions; D049452:Green Fluorescent Proteins; D008628:Mercury