Answer
Correct Answer: (1) C and D only
Explanation:
A. Restriction enzymes – Essential
They recognize specific sequences in double-stranded DNA and cut at precise locations. Vital for cutting both the DNA to be cloned and the vector DNA.
B. DNA ligase – Essential
DNA ligase joins broken DNA strands, sealing nicks between vector and inserted DNA during cloning.
C. DNA mutase – Not essential
Involved in rearranging functional groups within a molecule. Not used in standard cloning techniques.
D. DNA recombinase – Not essential
Facilitates DNA strand exchange between homologous sequences. Useful in recombination but not required for basic gene cloning.
E. DNA polymerase – Essential
Replicates DNA by synthesizing new strands from existing templates. Commonly used in PCR prior to cloning.
Conclusion: DNA mutase and DNA recombinase are not essential for gene cloning.
Correct Option: (1) C and D only