Helicase

Definition

Helicase is an essential enzyme in DNA replication that unwinds the double-stranded DNA, creating two single strands. This action is critical for allowing other enzymes to synthesize new complementary DNA strands.

5 Must Know Facts For Your Next Test

1. Helicase breaks hydrogen bonds between the nucleotide pairs to separate the DNA strands.
2. It functions at the replication fork, where active DNA synthesis occurs.
3. Helicase activity requires ATP to provide the necessary energy for unwinding.
4. Malfunction or mutations in helicase can lead to genetic disorders or impede replication processes.
5. Helicases are found in both prokaryotic and eukaryotic organisms, essential for their cellular division and genetic maintenance.

Review Questions

• What role does helicase play in DNA replication?
• Why is ATP necessary for helicase function?
• What could be the consequence of a non-functional helicase enzyme?

Related terms

DNA Polymerase:

An enzyme that synthesizes new DNA strands by adding nucleotides to a template strand.

Replication Fork:

The Y-shaped structure formed during DNA replication where the double helix is separated into single strands.

Single-Strand Binding Proteins (SSB): Proteins that bind to single-stranded DNA to prevent secondary structures and protect it during replication.