title: Construction of two lux-tagged Hg2+-specific biosensors and their luminescence performance.
abstract: Two Hg2+-specific biosensors were constructed using bacterial luciferase as reporter gene and plasmid-free Pseudomonas putida X4 and Enterobacter aerogenes NTG-01 as host strains. The performance of X4 biosensor was compared with that of NTG-01 biosensor in the same assay conditions. The maximum bioluminescence for X4 (pmerRluxCDABE-Kan) biosensor was found during the midexponential phase and that for NTG-01 (pmerRluxCDABE-Kan) was at the late exponential phase. The shortest induction time of two biosensors was 30 min. The maximum light signal output for NTG-01 and X4 sensors was observed at the incubation time of 5 and 4 h, respectively. The lowest detectable concentration of mercury by the two biosensors were both of 100 pM at 28 degrees C, pH 7 and an initial cell number of 10(6) CFU ml(-1). Cd2+, Zn2+, Co2+, Cu2+, and Pb2 + ions at nanomolar level did not interfere with the measurement by the biosensors. These results show that the sensitivity of the two biosensors is sufficient for the detection of Hg2+ under most contaminated environments.
authors.affiliation: State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.
authors.forename: Ya-Juan
authors.initials: YJ
authors.lastname: Fu
authors.forename: Wen-Li
authors.initials: WL
authors.lastname: Chen
authors.forename: Qiao-Yun
authors.initials: QY
authors.lastname: Huang
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D021902:Enterobacter aerogenes / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D017930:Genes, Reporter; D006863:Hydrogen-Ion Concentration; D049453:Luciferases, Bacterial / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D049449:Luminescence; D008628:Mercury / Q000032:analysis*; D016958:Pseudomonas putida / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D012680:Sensitivity and Specificity; D012989:Soil Pollutants / Q000032:analysis*; D013696:Temperature
chemical_list: D012989:Soil Pollutants; D049453:Luciferases, Bacterial; D008628:Mercury