Which enzyme is responsible for cutting DNA into pieces at specific sequences?

The enzyme responsible for cutting DNA into pieces at specific sequences is the restriction enzyme. These enzymes play a crucial role in molecular biology by recognizing specific short sequences of nucleotide bases in the DNA and cleaving the DNA at those sites. This characteristic allows restriction enzymes to act like molecular scissors, making it possible to isolate and manipulate genes for cloning, DNA fingerprinting, and various genetic analyses.

Restriction enzymes are fundamental tools in genetic engineering and molecular cloning, enabling researchers to create recombinant DNA by combining DNA from different sources. The specificity of these enzymes ensures that only the desired sequences are cut, providing precision in genetic manipulations.

In contrast, ligase is responsible for joining DNA fragments together, helicase unwinds the DNA double helix, and polymerase synthesizes new strands of DNA. Each of these enzymes has a distinct function that does not involve cutting DNA at specific sequences, which is why they do not fulfill the same role as restriction enzymes.