Genetic Engineering Based(A Plasmid)

the DNA of any transmissible agent (e.g. plasmid or virus) into which a segment of foreign DNA can be spliced in order to introduce the foreign DNA into cells of the agent's normal host and promote its replication and transcription therein. (1) Plasmid vectors contain (i) an origin of replication, so that the plasmid can be replicated; (ii) an antibiotic resistance gene to allow selection of transformed host cells; (iii) often, a ‘polylinker’ containing several different restriction enzyme recognition sites and a second marker gene (e.g. lacZ; see X‐gal), which will be inactivated when foreign DNA is inserted therein, thus allowing identification of transformants bearing plasmids containing inserts, rather than ‘empty’ vectors. Examples include pBR322 and the pUC vectors. See also expression vectors. (2) Bacteriophage vectors, usually based on lambda phage, can accommodate longer fragments of foreign DNA. In insertion vectors (e.g. λEMBL4) the foreign DNA is inserted into the phage DNA whole in replacement vectors (e.g. λEMBL4) the foreign DNA is ligated between two phage fragments, or arms. (3) Hybrid vectors, cosmids, phagemids and phasmids , with features of both plasmids and phage, have also been constructed.


http://science.jrank.org/pages/27228/cloning-vector-or-cloning-vehicle.html