DNA helicase is an essential enzyme that unwinds the double-stranded DNA by breaking the hydrogen bonds between the complementary bases, separating the two strands to create single-stranded DNA templates. This unwinding is crucial for processes such as DNA replication, repair, and recombination
. Functionally, DNA helicase uses energy derived from ATP hydrolysis to move directionally along the DNA strand, actively disrupting the double helix structure. This mechanical action allows other enzymes, like DNA polymerases, to access the single strands for copying or repair
. In DNA replication, helicase is recruited to the replication origin, where it unwinds the parental DNA strands at the replication fork, enabling the formation of replication bubbles. It coordinates with other proteins such as single-strand DNA-binding proteins to prevent the strands from reannealing and with topoisomerases to relieve supercoiling stress ahead of the fork
. In summary, DNA helicase:
- Separates the two strands of the DNA double helix by breaking hydrogen bonds
- Uses ATP energy to translocate along DNA and unwind it
- Provides single-stranded DNA templates necessary for replication, repair, and recombination
- Works in coordination with other proteins to ensure efficient DNA metabolism and genome stability
