Question

In order to isolate the DNA with the gene of interest from an animal cell, it needs to be in pure form, free from other macromolecules. The DNA molecules intertwine around histone proteins. Which of the following enzyme treatments will help to purify the DNA from the associated proteins?

• A. RNase
• B. Protease
• C. Chitinase
• D. DNase

Answer 1

The correct option is B Protease

DNA extraction refers to the process of obtaining the purified DNA from the cell.

It involves a series of steps with enzymatic treatments.

- As it is an animal cell, so no extra enzymatic treatment is required to remove the cell wall.

- Cell lysis is done by disrupting the cell membrane. This releases all the cellular components in the lysis buffer.

- RNase treatment is given to digest and remove any traces of RNA.

- The DNA is wrapped around proteins in structures called nucleosomes. In order to obtain protein-free DNA, it has to be treated with a protease enzyme.

During the DNA extraction process DNase treatment is not given as it will digest the DNA itself.

Fungal cells are protected by cell wall made up of chitin and chitinase enzymes helps in degradation of the cell wall.