Restriction Enzyme Digestion

The aim of this experiment was to investigate the effects of methylation on digestion of genomic DNA with different restriction enzyme concentrations.

We performed a genome prep assay on 2 different strains of E.Coli - a Dam positive strain (TOP10) and a Dam negative strain (GM2163). The DNA of the Dam positive strain is naturally methylated, whilst the DNA of the Dam negative strain was unmethylated. This allowed comparisons to be drawn between the amount of cleavage by restriction enzymes.

A restriction digest was performed using our 2 restriction enzymes (DpnII and TaqI) each at varying concentrations. The results can be seen below:

DpnII Restriction Digest

Here we can see clearly the differences between the Dam positive and negative strains.

DpnII Restriction Digest

Again, there are clear differences between the Dam positive and negative strains.