Screening and selecting transformed cells

Question 1

Why may not all host cells sucesfully take up a recombindant plasmid?

Answer 1

= the recombindant plasmid doesnt get inside the cell
= plasmid rejoins before the DNA frragment entered
= the dna fragment sticks to iyself instead of inserting into teh plasmid

Question 2

How can we recognise which bacteria sucesfully tok up the recombindan plasmid?

Answer 2

= marker genes
= anitiobit resitsnace genes
= genes coding for flurscent proteins
= genes coding for enzymes

Question 3

How do we dteermine withthe antiobuotc resistance?

Answer 3

= resistance to a particular antibiotic resistance gene is disrupted by the DNA fragment
= gene will not create a functional protien
=

Question 4

What do we do with the bacteria?

Answer 4

= grow bacteria on agar
= transfer bacteria to agar plate with the antiobiotic on it
= vacterua grow have plasmid inside of it as it has the gene making it resistance to the antibiotic,
= place fresh sterile velvet block, place on petri dish with other antibiotic, and if they grow on both they are resistant to both, if only resitsant to one must have the reconbindant dna

Question 5

How do we use the flourscent gene?

Answer 5

= the gene cods to create green flirscne tporein
= inserted into bacterial plasmid
= dna fragment inserted into the middle, so cannot be expressed and produce the protein
= grow bacteria and expose to UV light, the ones gene intact clow, but the bacteria thay do not grow, contain the recombindant plasmid

Question 6

How can we use the enzyme lactase?

Answer 6

= enzme lactae can convert substance from colourless to blue
= gene for this enzyme is inserted into the plasmid
= dna fragment is inserted nto the middle of te gene to disrpt it so cannot be expressed
= bacteria is now grown with the coolourless substance, colonlises that cannot make it change colour are the ones contain reco,bindant plasmi d