Question

a) You have prepared a batch of competent E coli cells and found its transformation efficiency is 10^6 per mu g plasmid DNA. A professional scientists prepared competent E. coli cells having a transformation efficiency of about 10^8 cells/mu g plasmid DNA Calculate % score of your E. coli transformation efficiency (T.E.).

b) Study the base of the DNA below. If EcoRI recognizes base sequence of GAATTC, write the DNA figments (showing base sequence) that will be produced after EcoRI digestion of this DNA.

5'ACGCGAATTGAATTCGATCGAATCCAGTAGCCGCAATTCCAAGAATTCTTC3’

3'TGCGCTTAACTTAAGCTAGCTTAGGTCATCGGCGTTAAGGTTCTTAAGAAG5"

Answer 1

a) Transformation efficiency of my plasmid = 106

Transformation efficiency of scientist plasmid = 108

Percentage of transformation efficiency = (106/ 108) X 100 = 1%

b)

5'ACGCGAATTGAATTCGATCGAATCCAGTAGCCGCAATTCCAAGAATTCTTC3’

3'TGCGCTTAACTTAAGCTAGCTTAGGTCATCGGCGTTAAGGTTCTTAAGAAG5"

ECoRI cuts the DNA at G/AATTC and CTTAA/G

So the fragments after digestion would be,

5'ACGCGAATTG AATTCGATCGAATCCAGTAGCCGCAATTCCAAG AATTCTTC3’

3'TGCGCTTAACTTAA GCTAGCTTAGGTCATCGGCGTTAAGGTTCTTAA GAAG5"

Totally three fragments will be produced by this enzyme.