Abstract

The growing interest of extremophiles results from the fact that their enzymes arestable and active under harsh environment conditions. These type of biocatalysts are attractivedue to the fact that can be used in industrial processes that were previously regarded asincompatible with biological materials. Among extremozymes the largest group constitutethermozymes. Currently it is estimated that approximately 40% of enzymes used in industrialsectors such as the production of food, detergents, pharmaceuticals, leather products anddiagnostics, waste management and recovery of silver are the proteases. The dominance of thisgroup on the production markets continue to rise. This involves the need to obtain new sourcesof proteases.The current study allowed to establish the possibility of using thermophilic bacteriaDeinococcus geothermalis as a source of proteolytic enzymes. The enzymes produced byDeinococcus geothermalis have unique characteristic such as temperature, chemical and pHstablity. Extracellular proteases produced by D.geothermalis exhibited highest activity at60°C, which was temperature higher of 15°C than in optimal conditions of bacteria's growthand at pH 9. After incubation at the 60°C for 1 h the enzyme affirmed of 92% activity of initialvalue, which prove that is thermal stable. The enzyme was stable in a range of pH from 6.0 to10. The study of inhibitor's impact suggests that enzyme produced by Deinococcusgeothermalis belong to serine proteases. The study of chemical compounds impact like Tween80 and Triton X-100 suggests that enzymes produced by Deinococcus geothermalis could beused as a component of detergents. Tween 80 and Triton X-100 slightly affected on catalyticproperties of proteases and caused only 3,2% and 9,71% decrease of activity. Under standardassay conditions, the apparent Km value of the enzyme toward azocasein was 1,64 mg/ml.

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