InterPro domain: IPR013986

This domain superfamily is found in DExx type DNA helicases, such as the hexameric essential helicases PcrA from Gram-positive bacteria and Rep and UvrD from Gram-negative bacteria [ 1 ]. PcrA is essential for cell growth in Bacillus species, as it is required for rolling circle replication, unwinding DNA using an active inchworm mechanism [ 2 ]. UvrD from Escherichia coli is a superfamily 1 (SF1) helicase involved in several DNA metabolic processes, including recombination and repair [ 3 ], while Rep affects the rate of replication fork progression in E. coli and is required for the replication of certain phages [ 4 ]. The domain is also found in the exodeoxyribonuclease V gamma chain, which has a wide variety of catalytic activities including ATP-dependent exonuclease, ATP-stimulated endonuclease, ATP-dependent helicase and DNA-dependent ATPase activities.

1. Essential bacterial helicases that counteract the toxicity of recombination proteins. EMBO J. 21, 3137-47
2. Directional loading and stimulation of PcrA helicase by the replication initiator protein RepD. J. Mol. Biol. 371, 336-48
3. A nonuniform stepping mechanism for E. coli UvrD monomer translocation along single-stranded DNA. Mol. Cell 26, 335-47
4. Rep helicase suppresses short-homology-dependent illegitimate recombination in Escherichia coli. Genes Cells 10, 1015-23