What do the enzymes gyrase and helicase do?

Helicases are used separate strands of a DNA double helix or a self-annealed RNA molecule using the energy from ATP hydrolysis, characterized by the breaking of hydrogen bonds between annealed nucleotide bases. They also function to remove nucleic acid-associated proteins and catalyze homologous DNA

gyrase is an enzyme that catalyzes the ATP-dependent negative super-coiling of double-stranded closed-circular DNA. Gyrase is a class of enzyme called topoisomerases that are involved in the control of topological transitions of DNA.