Question

You are cloning an aardvark gene, using a bacterial plasmid as a vector. The green diagram shows the plasmid, which contains the restriction site for the enzyme used in Figure 20.5. Above the plasmid is a segment of linear aardvark DNA that was synthesized using PCR. Diagram your cloning procedure, and show what would happen to these two molecules during each step. Use one color for the aardvark DNA and its bases and another color for those of the plasmid. Label each step and all 5’ and 3’ ends.

Short answer

According to figure 20.5, Hind III is the restriction enzyme that recognizes the nucleotide sequence 5’-GAAGCTT-3’. Both plasmid and aardvark genes are cleaved using this enzyme and gene fragments obtained are ligated and cloned in a bacterial host cell.

Step-by-step solution

DNA Vector

A single fragment of DNA of a gene can be cloned or its many copies can be produced by using recombinant DNA technology. For this purpose, a DNA fragment is attached to a vector that allows replication of the DNA fragments in a host organism.These vectors can be bacterial plasmids, viral or yeast-based.

Step 2: Plasmid

A plasmid is an extra-genomic DNA molecule in the bacterial cells that replicate freely from their chromosomal DNA. They are circular and double-stranded and contain genes for antibiotic resistance.Plasmids can also be used in recombinant DNA technology for cloning the desired gene segment.

Step 3: Cloning of aardvark gene using bacterial plasmid

Gene (aardvark gene) cloning procedure involves the fragmentation of the gene and a bacterial plasmid by a similar restriction enzyme that can be Hind III because both DNA have its recognition sequence.

After cleaving, both DNAs are ligated and a recombinant plasmid is formed. This is cloned in a bacterial cell.