How Can Genes Be Transferred Between Organisms?

• Genetic Engineering


  • Technique used to transfer genes from one organism to another
  • Individual genes are cut off from the cells of one organism and inserted into the cells of another organism of the same or different species
  • The transferred gene can express itself in the recipient organism.
  • The gene-of-interest is the gene to be transferred. A transgenic organism has a foreign gene inserted into its DNA.
• Vector


  A vector is a DNA molecule, virus or bacterium that is used to transfer the gene-of-interest into another organism.

  Plasmid :

  • A plasmid is a small circular DNA in a bacterium
  • It replicates independently of the bacterium’s DNA
  • Can be used as a vector.
• Restriction Enzymes and Sticky Ends

  • A restriction site is a segment of DNA that is recognised by a restriction enzyme
  • The restriction enzyme then cuts the restriction site to produce sticky ends.
  • The same restriction enzyme is added to the vector and the DNA containing the gene-of-interest, producing complementary sticky ends.
  • The sticky ends will bind together through complementary base pairing
  • DNA ligase seals the sticky ends and a recombinant DNA is formed.

  
• Artificial Selection


  • the selective breeding of a specific species with desired phenotype characteristics to produce organism with desirable traits
• Transgenic Organism

  • a cell that gains the function to produce certain substances that are otherwise not possible under normal conditions
  • has the gene-of-interest of another organism of the same or different species inserted into it, allowing it to have the desirable trait
• Factors to be kept constant for fermenters (Bioreactors)

  • temperature of the broth in the fermenter, to prevent enzymes of bacteria from denaturing
  • pH level of the broth, prevent enzymes of bacteria from denaturing
  • concentration of the nutrients so that transgenic bacteria can continue to grow and reproduce
  • concentration of oxygen