HerA is a DNA helicase able to utilize either 3' or 5' single-stranded DNA extensions for loading and subsequent DNA duplex unwinding. It forms a complex with NurA nuclease, this complex has the 5'-3' DNA end resection activity and is essential for cell viability in the crenarchaeon Sulfolobus islandicus. This entry represents the C-terminal domain of HerA which seems to be involved in the conversion of ATP hydrolysis into DNA translocation.