DNA helicases are molecular motor enzymes that use the energy of NTP hydrolysis to separate transiently energetic-ally stable duplex DNA into single strands. They are there-fore essential in nearly all DNA metabolic transactions. They act as essential molecular tools for the cellular machinery. Since the discovery of the first DNA helicase in Escherichia coliin1976, several havebeen isolated fromboth prokaryotic and eukaryotic systems. DNA helicases gener-ally bind to ssDNA or ssDNA/dsDNA junctions and translocate mainly unidirectionally along the bound strand anddisrupt the hydrogenbonds between the duplexes
