The luminous intensity of dark variant (S1) separated from photobacterium phosph oreum (A2) was 1/10 000 less than that of wild type. Ethidium bromide (EB) (0.6 mg/L), Mytomycin C (MC, 0.05 mg/L), 2 amino fluorene ...The luminous intensity of dark variant (S1) separated from photobacterium phosph oreum (A2) was 1/10 000 less than that of wild type. Ethidium bromide (EB) (0.6 mg/L), Mytomycin C (MC, 0.05 mg/L), 2 amino fluorene (2 AF, 1.0 mg/L) all cou ld strongly induce reversion mutation for S1 within 24 h and increase reversion ratio significantly. The results of experiments indicated that these revertants had stable genetic characteristic and the mutation may take place at gene levels . The mutagenesis to S1 caused by EB, MC and 2 AF was detected and it may be us ed as a new rapid, simple and sensitive method for gene toxicant monitoring.展开更多
A stable dark variant separated from photobacterium phosphoreum (A2) was fixed in agar-gel membrane and immobilized onto an exposed end of a fiber-optic linked with bioluminometer. The variant could emit a luminescent...A stable dark variant separated from photobacterium phosphoreum (A2) was fixed in agar-gel membrane and immobilized onto an exposed end of a fiber-optic linked with bioluminometer. The variant could emit a luminescent signal in the presence of genotoxic agents, such as Mitomycin C (MC). The performance of this whole-cell optical fiber sensor system was examined as a function of several parameters, including gel probe thickness, bacterial cell density, and diameter of the fiber-optic core and working temperature. An optimal response to a model genotoxicant, Mitomycin C, was achieved with agar-bacterial gel membrane: the thickness of gel membrane was about 5 mm; the cell density of bacteria in gel membrane was about 2.0×107 /ml; the diameter of fiber-optic core was 5.0 mm; the working temperature was 25 ℃. Under these optimized conditions, the response time was less than 10 h to Mitomycin C, with a lower detection threshold of 0.1 mg/L.展开更多
文摘The luminous intensity of dark variant (S1) separated from photobacterium phosph oreum (A2) was 1/10 000 less than that of wild type. Ethidium bromide (EB) (0.6 mg/L), Mytomycin C (MC, 0.05 mg/L), 2 amino fluorene (2 AF, 1.0 mg/L) all cou ld strongly induce reversion mutation for S1 within 24 h and increase reversion ratio significantly. The results of experiments indicated that these revertants had stable genetic characteristic and the mutation may take place at gene levels . The mutagenesis to S1 caused by EB, MC and 2 AF was detected and it may be us ed as a new rapid, simple and sensitive method for gene toxicant monitoring.
文摘A stable dark variant separated from photobacterium phosphoreum (A2) was fixed in agar-gel membrane and immobilized onto an exposed end of a fiber-optic linked with bioluminometer. The variant could emit a luminescent signal in the presence of genotoxic agents, such as Mitomycin C (MC). The performance of this whole-cell optical fiber sensor system was examined as a function of several parameters, including gel probe thickness, bacterial cell density, and diameter of the fiber-optic core and working temperature. An optimal response to a model genotoxicant, Mitomycin C, was achieved with agar-bacterial gel membrane: the thickness of gel membrane was about 5 mm; the cell density of bacteria in gel membrane was about 2.0×107 /ml; the diameter of fiber-optic core was 5.0 mm; the working temperature was 25 ℃. Under these optimized conditions, the response time was less than 10 h to Mitomycin C, with a lower detection threshold of 0.1 mg/L.
