By isolating the antibiotic resistance gene by cutting out a piece of DNA from a plasmid which was responsible for conferring antibiotic resistance .Please explain this clearly

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By isolating the antibiotic resistance gene by cutting out a piece of DNA from a plasmid which was responsible for conferring antibiotic resistance .Please explain this clearly

Asked by valavanvino1011 | 18 Jul, 2019, 08:21: PM

Expert Answer

Some genes called selectable markers help in selecting those host cells which contain the transformed vectors and eliminate the non-transformants.
Transformation is a process through which a piece of DNA is introduced in a host bacterium.
Generally, the genes encoding resistance to antibiotics such as tetracycline, ampicillin and kanamycin are useful selectable markers for E. coli.
Plasmid pBR322 has two resistance genes—ampicillin resistance (amp^R) and tetracycline resistance (tet^R)—which are considered useful for selectable markers.
If a recombinant DNA-bearing antibiotic resistance gene is transferred into E. coli cells, the host cells transform into antibiotic-resistant cells.
If such bacteria are transferred on a culture plate containing the respective antibiotic, only the resistant forms will grow and the others will die.
The antibiotic resistance gene acts as a selective marker in this case.

Answered by Sheetal Kolte | 19 Jul, 2019, 11:03: AM