Copyright Pearson Prentice Hall 13-3 Cell Transformation Recombinant DNA Host Cell DNA Target gene Modified Host Cell DNA Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Transforming Bacteria What happens during cell transformation? Copyright Pearson Prentice Hall

Transforming Bacteria During transformation, a cell takes in DNA from outside the cell. The external DNA becomes a component of the cell's DNA. Copyright Pearson Prentice Hall

Transforming Bacteria Foreign DNA is first joined to a small, circular DNA molecule known as a plasmid. Plasmids are found naturally in some bacteria and have been very useful for DNA transfer. Copyright Pearson Prentice Hall

Transforming Bacteria The plasmid has a genetic marker—a gene that makes it possible to distinguish bacteria that carry the plasmid (and the foreign DNA) from those that don't. Copyright Pearson Prentice Hall

Applications of Genetic Engineering If transformation is successful, the recombinant DNA is integrated into one of the chromosomes of the cell. Copyright Pearson Prentice Hall

Transforming Bacteria Gene for human growth hormone Recombinant DNA Gene for human growth hormone DNA recombination Human Cell Bacterial chromosome Sticky ends DNA insertion Bacteria cell During transformation, a cell incorporates DNA from outside the cell into its own DNA. One way to use bacteria to produce human growth hormone is to insert a human gene into bacterial DNA. The new combination of genes is then returned to a bacterial cell. The bacterial cell containing the gene replicates over and over. Bacteria cell containing gene for human growth hormone Plasmid Copyright Pearson Prentice Hall

Genetic Engineering and Recombinant DNA Plasmid is removed from donor (bacteria) DNA is removed from human cell The DNA is cut for insertion into the plasmid The plasmid is snipped to make a place to insert the human DNA A recombinant DNA is formed The plasmid is inserted into host/donor (bacteria) cell Host cell reproduces and contains the human DNA into the plasmid Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 13-3 Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 13-3 Plasmids can be used to transform bacteria only. plant cells only. plant, animal, and bacterial cells. animal cells only. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 13-3 An unknowing pioneer in the concept of cell transformation was Luther Burbank. Frederick Griffith. Oswald Avery. James Watson. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 13-3 One reason plasmids are useful in cell transformation is that they are found in all types of cells. prevent gene replication. counteract the presence of foreign DNA. have genetic markers indicating their presence. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 13-3 A common method of determining whether bacteria have taken in a recombinant plasmid is to introduce them into plant cells. introduce them into animal cells. treat them with an antibiotic. mix them with other bacteria that do not have the plasmid. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 13-3 Successful transformation of an animal or a plant cell involves the integration of recombinant DNA into the cell’s chromosome. changing the cell’s chromosomes into plasmids. treating the cell with antibiotics. destroying the cell wall in advance. Copyright Pearson Prentice Hall

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