Abstract
The importance of the mutagenic effects of certain chemicals around our environment needs to be emphasized. An experimental system suitable for demonstration in upper secondary school is described. The system uses bacteria to demonstrate DNA-damaging capacity and mutagenicity of certain chemicals. We used a pair of DNA-repair-deficient and DNA-repair-proficient Bacillus subtilis system, H17/M45, for screening the chemicals having the DNA-damaging capacity. The susceptibility of Bacillus subtilis H17 was compared with that of M45. The test chemicals were applied onto paper disks and placed it on the agar plate that streaked on the bacteria. To screen the mutagen, we used the Escherichia coli WP2s which is a DNA excision repair deficient and tryptophane requiring strain. We observed the ability of certain chemicals to induce reversion in this system.
