Project description:The number and type of synthetic chemicals that are being produced worldwide continues to increase significantly. While these industrial chemicals provide numerous benefits, there is no doubt that some have potential to damage the environment and health. Toxicity must be evaluated and use must be carefully controlled and monitored in order to minimize potential damage. DNA microarray technology has become an important new technique in toxicology. We are using the yeast Saccharomyces cerevisiae as a model organism for toxicological study because it is a simple, fast-growing eukaryote that has been thoroughly characterized. In order to evaluate toxicity by newly synthesized or mixture chemicals, toxicity-induced gene expression alteration profiles by known chemicals should be collected. Nitrophenols belong to the family of nitro compounds. There are three isomers, depending upon position of the functional groups at the aromatic ring: o- (CAS; 88-75-5), m- (CAS; 554-84-7) and p- (CAS; 100-02-7). It was reported that 4-nitrophenol is reported to be more toxic than 2- in animal test. In our yeast result, IC50 of o-, m- and p-nitrophenol was 3 mM, 5 mM, 1.5 mM, respectively, indicating highest toxic isomer was p-. p-Nitrophenol is reported to cause methemoglobinemia, and all isomers are suspected to be cardiovascular or blood toxicant, neurotoxicant. Keywords: stress response
