Nidialkova N. The peptidases of Bacillus thuringiensis IMV B-7324 with elastolytic and fibrinolytic activities

The thesis for a candidate's degree by speciality 03.00.07 - microbiology. - Zabolotny Institute of Microbiology and Virology of the National Academy of Sciences of Ukraine, Kiev, 2013. Bacillus thuringiensis IMV B-7324 peptidases with elastolytic and fibrinolytic activities were studied. In order to increase maximal biosynthesis of the peptidases with elastolytic and fibrinolytic activities it was optimized the nutrient medium and cultural conditions of the producer using a mathematical planning methods of experiments. This made a possibility to increase the elastolytic and fibrinolytic activities in 25.7 and 29.0 times respectively. Both enzymes were isolated and purified to a homogeneous state. The peptidase 1 belongs to the metallactivated serine peptidases and displays a broad substrate specificity to elastin, fibrin, collagen, fibrinogen and casein. The peptidase 2 hydrolyzes fibrin, collagen, fibrinogen and casein. It was established that enzymes differ in molecular weight, component composition, sensitivity to the cations and anions. It was first demonstrated the stabilizing effect of arginine, valine, lysine, leucine, alanine, isoleucine, glutamic and aspartic acids on the activity of peptidase 1 and 2 B. thuringiensis ІМV В-7324. It was shown the stabilizing action of Escherichia coli L-19 lipopolysaccharide and activated effect of a number of cobalt(II, III) complexes with derivatives of dithiocarbamic acid on B. thuringiensis ІМV В-7324 peptidase 1 and 2 activities.