helicase

Examples of helicase in the following topics:

• DNA Replication in Eukaryotes

  • Two copies of an enzyme called helicase are among the proteins recruited to the origin.
  • Each helicase unwinds and separates the DNA helix into single-stranded DNA.
  • The "leading strand" is synthesized continuously toward the replication fork as helicase unwinds the template double-stranded DNA.
  • The "lagging strand" is synthesized in the direction away from the replication fork and away from the DNA helicase unwinds.
  • A replication fork is formed by the opening of the origin of replication; helicase separates the DNA strands.

• Generalized Recombination and RecA

  • After RecBCD binds the DNA end, the RecB and RecD subunits begin unzipping the DNA duplex through helicase activity.
  • This is likely because the slower RecB helicase unwinds the DNA after Chi, rather than the faster RecD helicase, which unwinds the DNA before Chi.
  • Step 2: RecBCD initiates unwinding of the DNA duplex through ATP-dependent helicase activity.

• Biology: DNA Structure and Replication

  • When DNA replicates, as it does in cellular reproduction, it is first "unzipped" by any of a number of enzymes known as DNA Helicases.

• DNA Replication in Prokaryotes

  • An enzyme called helicase unwinds the DNA by breaking the hydrogen bonds between the nitrogenous base pairs.
  • A replication fork is formed when helicase separates the DNA strands at the origin of replication.

• Elongation and Termination in Eukaryotes

  • Specific subunits within the protein allow RNA Polymerase II to act as its own helicase, sliding clamp, single-stranded DNA binding protein, as well as carry out other functions.

• The Secondary & Tertiary Structures of DNA

  • Helicase: This enzyme assists the unwinding.