Question

Isolation of DNA from a fungal cell involves the use of enzyme

• A. Lysozyme
• B. Chitinase
• C. Eco RI
• D. Hind II

Answer 1

The correct option is B Chitinase

Isolation of genetic material
The first step in forming the rDNA in recombinant DNA technology is isolating the DNA of interest from the cell.

Fungal cell wall digestion
Fungal cell walls contain chitin that can be digested by chitinase enzymes.

Bacterial cell wall digestion
Bacterial cell wall contains peptidoglycans and lipids. It is broken down by using the enzyme lysozyme.

Restriction endonucleases
Restriction endonucleases are the enzymes which cleave the DNA by digesting phosphodiester bonds at the specific sequences within the DNA. Examples include EcoR I, Hind II etc.

EcoR I
EcoR I is a restriction endonuclease obtained from Escherichia coli, that recognises the palindromic sequence 5' - GAATTC - 3' and makes a cut between G and A on both the strands to form a sticky end AATT.

Hind II
Hind II is the restriction endonuclease from Haemophilus influenzae with the recognition sequence 5’ - GTCGAC - 3’.

Final answer
a. Chitinase.