| 摘要 |
PURPOSE:To obtain a new nitro reductase gene, isolated from Escherichia coli, coding for a nitro reductase reducing nitro group and useful for improving the sensitivity for detecting a substance having the mutagenicity or carcinogenicity such as a nitroarene. CONSTITUTION:This new nitro reductase gene is obtained by culturing an Escherichia coli C600 strain at 37 deg.C in a culture medium overnight, then centrifuging the resultant culture, collecting microbial cells, supsending the collected microbial cells in a tris hydrochloric acid EDTA buffer solution, treating the suspended microbial cells with a lysozyme and proteinase K, carrying out the bacteriolysis, treating the lysed microbial cells with phenol, precipitating the treated microbial cells with ethanol, recovering a genomic DNA and then performing the amplifying reaction with a synthetic oligonucleotide primer having a partial amino acid sequence of a flavin reductase having the homology with the nitro reductase gene. The resultant nitro reductase gene comprises a DNA having a base sequence of 840 sequence length composed of 217 amino acids and is useful for improving the sensitivity for detecting a mutagenic or a carcinogenic substance. |
