Characteristics of properties of carbohydrase enzyme complexes Bacillus subtilis strain

¹ All-Russian Research Institute of Phytopathology, Laboratory of biologically active substances, 143050 Odintsovo, Russia
² Federal Center for Toxicological, Radiation and Biological Safety, Laboratory of Cell Cultures and Nutrient Media, 420075 Kazan, Russia

^* Corresponding author: tanirtashir@mail.ru

Abstract

In this study, we have obtained two enzymes from the group of carbohydrases, cellulase and hemicellulase, secreted by vegetative cells of the B. subtilis strain, and comparatively characterized their properties in order to determine the possibility of further use of the bacillus and its metabolic products as safe biopesticides Homogeneous cellulase with a specific activity of 69.8 U/mg protein was isolated and purified electrophoretically from the culture liquid of B. subtilis by precipitation with ammonium sulfate, ion exchange chromatography, followed by purification by gel filtration. The molecular weight of the native cellulase molecule, determined by SDS-Na-PAGE electrophoresis and gel filtration, was established to be 34.0 kDa, and it was found that the enzyme consists of one subunit. Bacillus carbohydrases functioned in the temperature range (from 40 to 60 °C) and pH values (from 5.0 to 6.0). The enzyme was characterized by high stability of pH values from 3.0 to 9.0 (optimum pH 6.0) and temperatures from 20 to 75 ° C (temperature optimum from 53 to 59 ° C), respectively. A comparative study of the properties of cellulase and hemicellulase from the producer B. subtilis revealed differences in their structure and physicochemical properties: cellulase of the strain was a more thermostable and alkali-resistant protein. These results open up prospects for further study of the B. subtilis strain and its metabolic products - cellulolytic and hemicellulolytic enzymes, for potential use as an environmentally friendly means for the control of phytopathogens of agricultural crops.