Three Phase of the Development of Plasmid Clonign Vectors, First Phase the Vectors, Size of Vector, Larger Plasmids Replicate, Recombinant Clones

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Cloning and Expression Vectors Cloning and Expression Vectors Introduction Cloning Vectors for Recombinant DNA Plasmids as Vectors Three Phases of the Development of Plasmid Cloning Vectors Alpha-Complementation for Screening Using "blue-white"Clonies Nonsense Suppressors to Complement Termination Codons in Vectors E.Coli Plasmid Vectors pBR322 and pBr327 Vectors pUC Vectors pSP64-pSP65 pGEM-3, pGEM-4, pGEM-3Z, pGEM-4Z ΠAN13 from ΠAN7 Yeast Plasmid Vectors Retriever Vectors Agrobacterium Plasmid Vectors Lambda Phage (λ)Vectors Lambda Phage (Lysis and Lysogeny) Genetic Markers for the Selection and Screening of λ Vectors Development of Lambda (λ)Phage Vectors Insertion λ Vectors Replacement λ Vectors M13 Phage as a Vector for DNA Sequencing M13-vectors-of-mp-Series Hosts for M13 Vectors Cosmids as Vectors Phagemids as Vectors Phagemids pUC118 and pUC119 Phagemid pBluesript IIKS

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Three phases of the development of plasmid cloning vectors.

Development of plasmid vectors proceeded chronologically in the following three phases. (1) In the first phase, the vectors that were made available during 1973-1976 included pSC101, Co1E1 and pCR1, all of them suffering with the following drawbacks: (i) they replicated poorly, (ii) they carried unsuitable selectable markers and (iii) they carried not more than two restriction sites for cloning.

These drawbacks were taken care of in pBR313, but it was unnecessarily large, half of its DNA being non-essential. This was reduced in size giving rise to pBR322 (4.362kb; both pBR313 and pBR322 were produced in 1977), which remained popular for many years.

In the second phase, the size of plasmid vectors was greatly reduced, because the efficiency of transformation is inversely related to the size of vector, and also because larger plasmids replicate to lower copy number. A number of derivatives of pBR322 were thus released, which included pA TI53, pXf3, pBR327, etc. They made use of antibiotic resistance for selecting recombinant clones. The third phase of the development of plasmid vectors involved (i) incorporation of Hindi fragment of β-galcatosidase gene to permit selection through blue/white colonies due to alpha-complementation (e.g., pUC vectors; see later for alpha complementation).

(ii) incorporation of DNA. sequences from single stranded M 13 phage, for generation of single stranded DNA templates for sequencing, e.g. phagemid vectors, (iii) incorporation of promoter DNA sequences for transcription in vitro, e.g. pGEM vectors .or (iv) incorporation of high expression promoters for expression of large amounts of foreign proteins (e.g. a variety of expression vectors).

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BACs and PACs as Vectors for Cloning large DNA Segments (100-300 kb) Bacterial Artificial Chromosomes (BACs) P1-derived Artificial Chromosomes (PACs) Plant and Animal viruses as Vectors Plant Viruses (Cauliflower Mosaic virus or CaMV and Geminiviruses) Animal Viruses Transposons as Vectors Transposons of Higher Plants (Ac/Dc or Mul of Maize) Transposons of drosophila (P elements) YAC and MAC Vectors for Cloning very large DNA Segments (1000 kb) Yeast Artificial Chromosomes (YACs) Mammalian Artificial chromosomes (MACs) Expression Vectors Promoters Nopaline Synthase (nos) Promoter from T-DNA Dual Promoter of Mannopine Synthase (mas) genes 1 and 2 35S Promoter of CaMV Polyhedrin Promoter from Baculovirus Expression Cassettes Baculovirus and Expression Vector System for Insect Cells Virus Expression Vectors for Mammalian Cells Binary and Shuttle Vectors