Question

Define biotechnology. Mentioning all steps and explain only first two steps of recombinant DNA technology in detail. Give diagrammatic representation of recombinant DNA technology.

Answer 1

1. Identification and isolation: A gene of interest (DNA fragment) is isolated from cells that have been grown in laboratory culture. Both the human DNA and the plasmid are treated with the same restriction enzyme to produce identical sticky ends. The restriction enzyme cuts the plasmid DNA at its single recognition sequence, disrupting the antibiotic resistance gene.

2. Joining of the gene with the vector: The DNA fragment is mixed with plasmid and the complementary sticky ends are attached to each other by base pairing. The enzyme DNA- ligase is added to bond the sticky ends.

3. The introduction of a vector into suitable organism: The recombinant plasmid or molecular clone is introduced into a bacterial cell by adding the DNA to a bacterial culture. Under the right condition, some bacteria will take up the plasmid from solution by the process transformation.

4. Selection of recombinant cell: Transformed cells from nontransformed cells are selected using antibiotic resistance method.

5. Multiplication of gene of interest: Recombinant DNA molecules are then multiply to obtain product from the gene of interest.