Storage of Bacillus anthracis strain using low temperature preservation method

Abstract

Storage of industrially valuable strains of microorganisms is one of the strategic tasks of modern science and the biological industry. The production and timely implementation of therapeutic, preventive and diagnostic drugs against anthrax contributes to maintaining a stable epizootic situation in Russia for this disease. Therefore, the development and study of methods for storing industrially valuable strains of Bacillus anthracis is an important research work that allows preserving and preserving the unique biological properties of the cells of this pathogen. The purpose of this work was to study the preservation of the viability and biological properties of the Bacillus anthracis strain after 12 months of low-temperature preservation. The strain K-STI-79 of the causative agent of anthrax was used in the work. The strain was stored for 12 months at a temperature of minus 70 C in two cryoprotective media: 15% glycerin solution with 15% glucose solution and 30% neutral glycerin solution in saline solution. After 6 and 12 months of storage, the cells were removed from preservation, thawed at 37 C, tenfold dilutions were made in sterile saline solution and seeded to determine the concentration of viable cells. The safety of the biological properties of the pathogen was studied according to MUC 4.2.2413-08. As a result of the work, it was found that the selected cryoprotectors and the temperature regime of storage allowed to keep a high number of cells in a viable state, which did not significantly differ statistically from the initial concentration. The study of the biological properties of the strain showed their compliance with passport data. The conducted work demonstrates the possibility of effective use of the applied scheme of low-temperature preservation of Bacillus anthracis strains for 12 months.