1Department of Nanobiotechnology, School of Biological Sciences, Tarbiat Modares University, Tehran, Iran
2Department of Molecular Genetics, School of Biological Sciences, Tarbiat Modares University, Tehran, Iran
3Department of Resin and Additives, Institute for Color Science and Technology, Tehran, Iran
4Department of Biophysics, School of Biological Sciences, Tarbiat Modares University, Tehran, Iran
5Laboratory of Membrane Biophysics, Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran
CaCl2 treatment followed by heat shock is the most common method for artificial transformation. Here, the cells were transformed using CaCl2 treatment either with heat shock (standard protocol) or without heat shock (lab protocol) to comprehend the difference in transformation efficiency. The BL21 strain of Escherichia coli (E. coli) was being susceptible using CaCl2 treatment. Some Cells were kept at -80 oC while the others were kept at 4 ̊C. Afterwards the susceptible cells were transformed using either standard or lab protocol. The transformation efficiency between cells experienced heat shock and those were not influenced by heat shock was almost the same. Moreover, regardless of transformation protocol, the cells kept at 4 ̊C were transformed more efficiently in compared to those were kept at -80 oC.
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