Transformation efficiency on E. coli in response to different bivalent salts
Abstract
Bacterial transformation is the process of up taking foreign DNA molecules by bacterial cells. Bacteria, which are able to up take such foreign DNA are called “competent” cell. Foreign DNA carrying antibiotic resistance gene can be expressed in the bacteria and transforming the bacteria from antibiotic sensitive to antibiotic resistance. Such transformed bacteria can easily be isolated. The efficiency of the transformation plays a critical role in recombinant DNA technology. Several methods have been developed to improve the transformation efficiency. In our work we have studied the transformation efficiency on strains of E. coli and in response to different bivalents salts at different concentrations. All the experiments revealed that transformation efficiency was highest on E. coli DH5α strain in 50 mM CaCl2 concentration. Comparing to the other E. coli and bivalents salts concentration, 50 mM CaCl2, resulted in much faster growth of transformed bacteria. Thus, our results suggest that E. coli DH5α strain and CaCl2 can be used as an effective agent for the transformation technique.
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