Vector recombinant DNA

Workers in the early 1970s recognized that restriction enzymes provided tools not only for DNA mapping but also for constmction of new DNA species not found in nature. A collection of recombinant DNA species consisting of many passenger sequences joined to identical vector molecules is called a hbrary. Individual recombinant DNAs are isolated from single clones of the Hbrary for detailed analysis and manipulation. 

Fig. 3. Constmetion of a recombinant DNA by joining vector and passenger fragments where (I I I I I I) represent sticky ends. Both A and B genes represent selectable traits, so that introduction of foreign DNA in B gene leads to the loss of an identifiable function. REP represents repHcation and...

Plasmids are small, circular DNAs that range in size from 2 to approximately 100 kb. They also can be amplified to approximately 20 copies per cell. In addition, plasmids can be introduced into bacterial cells, although less efficiently than phage vectors. Some plasmids can be used to introduce recombinant DNA into yeast cells. 

One usually tries to adjust experimental conditions so that only one plasmid or phage is introduced into a single cell. When that cell replicates on a plate of nutrient agar, it will produce millions of cells until a colony becomes visible to the naked eye. If cells are sufficiently diluted before they are spread onto the plate, each colony will consist of a clone derived from a single ancestral cell. If each cell originally contained only one copy of the phage or plasmid vector, each colony will contain recombinant DNA that is homogeneous. That is, each colony will contain cloned DNA. 

Most of the known microorganisms to be active for BDS (by the date that patent [408] was introduced), were considered in this invention. Furthermore, their mutational or engineered derivatives, enzymes, cell-free extracts, recombinant enzymes, recombinant DNA, plasmids, vectors, and fragments were also incorporated in the intellectual property document. The mentioned operating conditions regard ambient temperature, mechanical agitation and a 1 9 biocatalyst/petroleum ratio. 

Vector Plasmid or other self-replicating DNA molecule that transfers DNA between cells in nature or in recombinant DNA technology, [nih]... 

Advances in genomics, molecular biology, and recombinant technology have provided new directions for the discovery, development, and manufacture of vaccines. One of the current approaches is a minimalist strategy to decouple the virulence and immunity functions. The aim is to use only the immunity part to confer protection, so that the vaccine is safe to be administered. The approach can be divided into subunit, vector-based, DNA, and peptide vaccines. 

The vector is cut with the restriction endonuclease and mixed with the DNA restriction fragments to be cloned. As shown in Figure 1-6-3, once the vectors have combined with one of the restriction fragments, DNA ligase is used to form permanent PDE bonds between the fragment and the vector. This produces recombinant DNA. 

Cytoplasmic mRNA is isolated from a cell known to express the desired gene. Reverse transcriptase, along with other components (Figure 1-6-4), is used in vitro to produce double-stranded cDNA that is subsequently recombined with a chosen vector to produce the recombinant DNA for cloning. In this approach ... 

Vectors for recombinant DNA and cloning Plasmid pBR322 Restriction site Replication origin Resistance to antibiotic(s) Expression vector also requires Promoter Shine-Dalgarno sequence Other vectors phage, YACs... 

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