Ryzhko I. Alkaline peptide hydrolase of Drosophila melanogaster in the ontogeny of flies in the condition of environment polluted by heavy metal salts

The thesis is devoted to the study of biochemical properties of alkaline peptide hydrolase from the intestines of Drosophila flies and investigation of vital parameters in flies' ontogenesis, while keeping them in standard conditions and in the presence of heavy metals. It was installed that the activity of alkaline peptide hydrolase altered under ontogenesis: high esterase activity in the larval stage of development and amidase - adult fly of Normal line, high amidase activity in the larval stage and its absence in adult flies - in Meller-5 line. Alkaline peptide hydrolase of lines Normal and Meller-5 is similar to: molecular weight, pH optimum, substrate specificity, and response to the negative influence of CoCl2, CuCl2, ZnCl2 and CdCl2 and differs in optimum pH, optimum temperature and affinity to the substrate BAPNA. Severity of adverse effects of heavy metals on the activity of alkaline peptide hydrolase depends on the genotype of flies, stages of development and used salt. The activity of alkaline peptide hydrolase, synchronicity and life duration of flies, their fecundity and survival negatively correlated with increasing concentrations of heavy metals. The activity of alkaline peptide hydrolase Drosophila and individual development indicators can be used as markers for assessment of environmental pollution by heavy metals salts