Vector
A Vector acts as a template for the cloning of a specific gene. This gene needs to be inserted into the vector by recombinant DNA, before the vector can be inserted into a target host cell. [1]
Vectors are essential components for recombinant DNA technology. They act as the vehicle to carry recombinant DNA into the target host cell.
Vectors have special restriction sites onto which the recombinant DNA can insert itself. They are relatively easy to manipulate and introduce into the target host cell. Another important property of vectors is that they can be an efficient origin of replication.
The most common types of vectors are plasmid (which are circular pieces of DNA naturally found in bacteria) [2], viruses and cosmids (a plasmid containing cos sites). A plasmid can be linear or circular and is always doube stranded
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