Question

1- Why is it necessary to denature proteins in the DNA purification protocol?

2- What reagent accomplishes the denaturation? What does it mean when we say a protein is denatured?

3- How can you purify DNA? What are the steps? What are the reasons for each step?

Answer 1

Question 1

It is necessary to denature proteins in the DNA purification protocol because it help to degrade proteins that can contaminate DNA during DNA extraction.

Question 2

The reagent used for denaturation of the protein are urea and guanidium chloride. These molecules break the bonds present in protein to denature them. Denaturating of protein means breaking the 3D structure of the protein into amino acid sequence.

Question 3

Purification of the DNA involve lysating the DNA sample with appropriate procedure and isolating nucleic acid . Steps of DNA extraction are:

1. Lysating: involve breaking of cell and nucleus membrane to release DNA.

2. Precipitation: this step in needed to precipate DNA

3. Purification: the DNA is purified from contaminants in order to get pure DNA.