Hsp 104 expression and morphological changes associated with disinfectants in Saccharomyces cerevisiae: Environmental bioassay using stress response

Abstract

On exposure of Saccharomyces cerevisiae to sublethal concentrations of disinfectants such as TPN, Thiuram, Captan and Oxine-copper; 70-, 90-kDa proteins and heat-shock protein Hsp104 were induced without morphological changes. Considering these stress proteins as critical signs, we can determine how cells are damaged by pesticides under sublethal conditions. Furthermore, Hsp104-lacZ hybrid gene (a lacZ gene put under control of Hsp104 promoter) in S. cerevisiae was sensitively expressed in the presence of sublethal concentrations of these disinfectants by measuring the relative β-galactosidase activity. It follows that not only monitoring the growth phase or the induction of synthesized proteins but also detecting the level of gene expression shows the chemical stress response rapidly, conveniently and reproducibly. We conclude that the use of a yeast strain with a stress reporter gene is a novel and simple bioassay relative to human health and to the ecosystem in general.