Cloning

Cloning is a technique for recombination of DNA, with which a DNA fragment is inserted into a circular DNA molecule (cloning vector) by a ligase enzyme (ligation). The ligation products are brought into competent bacterial strains (transformation). The competent cells duplicate the recombined cloning vectors (e.g. plasmids) during growth and pass the copies on to their daughter generations. Plated on an agar medium the transformed cells build up colonies of genetically identical clones, which contain the recombined DNA.


Ligation



Heat shock transformation

Materials and solutions:

SOB medium (pH 7.2-7.4) 0.5% Yeast extract 2% Trypton 10 mM NaCl 2.5 mM KCl autoclave

SOC medium 10 mM MgSO4 10 mM MgCL2 20 mM Glucose sterile MgSO4, MgCL2, and glucose solutions in autoclaved SOB.

(Continue with cloning methods on next page)

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