DNA Analysis, Extraction & Visualisation of DNA using Agarose Gel Electrophoresis.

Question

1- A solution of Lambda DNA has a concentration of 0.1mg/ ml. How much DNA (in mg) do we have in a 4 ml sample?
2. Given that lambda has a genome size of 50 Kb, how many complete lambda genomes are present in the 4 ml volume from Question 1? (1 Kb = 1,000 base pairs; 1 Kb = 1.1 x 10-12 mg)

Answer 1

Hi Sara,

 

1-A is simple multiplication, if 1 ml has 0.1 mg then 4 ml has;

 

0.1*4 that is 0.4 mg.

 

Lambda genome is 50 kb, however, lambda phage grows in bacterial cells. During the process of DNA isolation, there would be some bacterial DNA as well and that needs to be considered. nevertheless, you can calculate the number of genomes in 0.4 mg or 400 ug DNA based on the equation that you have included above, you mayjust assume that  solution does not have any contaminating bacterial DNA.

 

Hope it helps.