2. • A plasmid is a genetic structure in a cell that can
replicate independently of the chromosomes,
typically a small circular DNA strand in the
cytoplasm of a bacterium or protozoan.
• Plasmids are much used in the laboratory
manipulation of genes.
• http://www.youtube.com/watch?v=GNMJBMtKK
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3. • Plasmids are easy to manipulate and isolate
using bacteria. They can be inserted to
mammals genomes, allowing you to introduce
genes into an organism by using bacteria. This
type of plasmid is the basis of recombinant DNA
technology.
4. • Stringent Plasmids
• Replicate only when the chromosome
replicates
• Relaxed Plasmids
• Replicate on their own
5. • Fertility Plasmids
• Contain transfer genes and are capable of
conjugation
• Resistance Plasmids
• Contain genes that can build resistance to
antibiotics or poisons and help bacteria
produce pili.
• Col Plasmids
• Contain genes that code for proteins that kill
other bacteria
• Degradative Plasmids
• Allows to digest unusual substances
• Virulence Plasmids
• Turn bacterium into a pathogen
6. • Supercoiled
• DNA is one but has a twist in it causing it to be more compact
• Supercoiled Denatured
• Less compact then supercoiled
• Linear
• DNA has free ends
• Nicked Open-Circular
• DNA has a strand cut
• Relaxed Circular
• DNA is intact as one
7. 1. Mutate
• Use a restriction enzyme to cut out portions of one genome and
insert them into a plasmid
2. Select
• Use genetic markers, the one that is resistant to antibiotics can
be added to the gene that is being inserted into the plasmid
3. Isolate
• Separate the plasmids
4. Transform
• Transform them into cells where they become vectors to
transport foreign genes
