Efficacy of genetic transformation of E.coli field and reference (ATCC 8739) strains at different concentrations of CaCl₂ for creation of Gene libraries

Scientific Center of Agrobiotechnology, ANAU Armenian National Agrarian University, 74, Teryan, Yerevan, 0009, Armenia

^* Corresponding author: tatev.aloyan20@mail.ru

Abstract

The importance of genetic transformation in various fields of biological research, and especially in the process of gene libraries formation, is very important. It has been proven by numerous studies that during the phase of obtaining competent cells, Ca²⁺ ions neutralize the electrostatic repulsion of membrane proteins and DNA of the bacterial cell, thereby stimulating the introduction of foreign DNA into the membrane pores. Our research aimed to elucidate the maximum efficiency of transformation in field and ATCC 8739 reference strains of E.coli at 0.05; 0.1 and 0.15 M concentrations of CaCL₂. Microbiological, molecular-biological modern methods were used in the experimental studies. From the research results, it became evident that the efficiency of genetic transformation increases with the addition of concentration of CaCL₂ and reaches the maximum at 0.1 M. Among the studied strains of E.coli, at 0.05 and 0.1 M concentrations of CaCL₂, the highest efficiency was recorded in the field strain. At a 0.15 M concentration of CaCL₂, the transformation efficiency in the field and reference strains is highly variable due to the size of the genomic DNA of the internalizing bacteria and the number of restriction sites.