Week 5: Transformation of Bacteria Flashcards
what is transformation?
uptake and expression of free DNA by cells
what is competence?
state where cells can uptake nakd DNA
how to make a bacterial cell competent?
we can induce competence by making the membrane permeable to DNA
why do we use calcium for transforming?
neutralize the negative charge on the bacterial cell surface
what two things do we do to transform bacteria?
calcium and heat shock
why do we use heat shock for transforming?
:O
heat shock is used to open bacterial pores to allow the DNA to go into the cell, cells are then kept cold and then put at 42 degrees
what is a plasmid?
a plasmid is a small circular piece of double-stranded DNA that has an origin of replication.
what are plasmids used for?
as vehicles to introduce foraging DNA into organisms
name three applications of plasmids
- genetic engineering
- cloning human genes
- protein production like insulin
describe how antibiotic resistance would look on a plate?
plated on agar that had ampicillin on it because plasmid had Amp resistance gene, and only those resistant to it because of incorporating plasmid would be able to grow
what is GFP expression?
tested plates under UV light, and those that had the GFP expression would glow under the light
what are the controls for transformation experiments? why are they significant?
a no DNA control, which showed that the genes that emerged weren’t spontaneous mutations
