Vector, cloning

Bacterial plasmids are small, circular, duplex DNA molecules whose natural function is to confer antibiotic resistance to the host cell. Plasmids have several properties that make them extremely useful as cloning vectors. They exist as single or multiple copies within the bacterium and replicate independently from the bacterial DNA. The complete DNA sequence of many plasmids is known hence, the precise location of restriction enzyme... 

Table 40-4. Cloning capacities of common cloning vectors.

The combination of restriction enzymes and various cloning vectors allows the entire genome of an organism to be packed into a vector. A collection of these dif-... 

PAC A high capacity (70-95 kb) cloning vector based upon the lytic E. colt bacteriophage PI that replicates in bacteria as an extrachromosomal element. 

Fig. 24.1 The requirement for a cloning vector (A) fragments of DNA introduced into the hacterium hy transformation do not undergo replication and gradually are diluted out of the population (B) DNA fragments introduced into plasmids are inherited hy both daughter progeny cell division.

Plasmid An extracbromosomal circular DNA molecule in bacteria. Often used as cloning vector. 

Construction of a broad host range cloning vector and its use in the genetic anlysis of Rhizobium mutants. Gene 18 289-296... 

Yanisch-Perron, C., Vieira, J. and Messing, J. 1985. Improved M13 phage cloning vectors and host strains nucleotide sequences of the M13mpl8 and pUCl9 vectors. Gene 33 103-1 19. 

Figure 4.4. Schematic illustration of directional topoisomerase cloning of PCR products into the pUNI vector. The PCR product to be cloned has the sequence 5 -CACC appended at the 5 end to direct the orientation of cloning. The Vaccinia virus topoisomerase I enzyme forms a covalent adduct with the cloning vector to create a cloning competent plasmid construct. The loxP site is 5 to the insertion site. The vector and PCR product are designed to fuse the ORF in-frame with loxP.

A vector (or cloning vector) is any DNA molecule (or fragment) capable of autonomous replication within a host cell into which other DNA sequences can be inserted and thus amplified. 

Integration of the various fragments generated into cloning vectors, which are themselves small DNA molecules capable of self-replication. Typically, these are plasmids or viral DNAs and the composite or engineered DNA molecules generated are called rDNA. 

An essential feature of the cloning vector used is that it must be capable of self-replication in the cell into which it is introduced, which is usually E. coli. Two of the most commonly used types of vector in conjunction with E. coli are plasmids and bacteriophage X. Plasmids are circular extra-chromosomal DNA molecules, generally between 5000 and 350 0000 bp in length, that are found naturally in a wide range of bacteria. They generally house several... 

See also Embryo cloning Cloning vectors, for DNA fragments, 22 504-506... 

Lambda-cyhalothrin, in microcapsule formulations, 7 564t Lambda-derived cloning vectors, 12 504-506 Lambda sensor, 10 56 Lambent, commercial defoamer, 3 24 It Lambert-Beer-Bouguer law, 23 126. See also Beer s Law... 

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