NEETZoologyBiotechnology - Principles and Processes
A researcher is attempting to isolate pure DNA from a fungal cell for recombinant DNA technology. Which of the following represents the correct combination of treatments required to successfully extract and precipitate the purified DNA?
Options
- ACellulase, protease, ribonuclease, and chilled ethanol
- BChitinase, protease, deoxyribonuclease, and chilled ethanol
- CChitinase, protease, ribonuclease, and chilled ethanol
- DLysozyme, ribonuclease, and chilled ethanol
Correct answer
C. Chitinase, protease, ribonuclease, and chilled ethanol
Step-by-step solution
To isolate DNA from a fungal cell, the cell wall must first be broken down. Fungal cell walls are composed of chitin, so the enzyme chitinase is required (cellulase is for plant cells and lysozyme is for bacterial cells). Once the cell is lysed, the extract contains macromolecules like RNA and proteins along with DNA. RNA is removed by treatment with ribonuclease, and proteins are removed by treatment with protease. Deoxyribonuclease (DNase) cannot be used as it would degrade the target DNA itself. Finally, the pur