Two ligation reactions between a vector and an insert are pr

Two ligation reactions between a vector and an insert are prepared. In one case (\"A\") the ligation was done with a dephosphorylated vector and in a second case (\"B\") the vector had not been dephosphorylated. Transformation in bacteria of equal amounts of DNA from the two ligation reactions yielded the following results:

Transformation of ligation mixture \"A\": 50 colonies

Transformation of ligation \"B\": 5000 colonies

Given the results obtained, what is the minimum number of colonies that must be screened in the transformation of ligation mixture \"B\" to find one recombinant clone?

Solution

Transformation of ligation mixture A = 50 colonies

Transformation of ligation B = 5000 colonies

minium number of colonies = 50,000

recombinat clone   = 1000