Superfamily: RuvA domain 2-like

duplication: contains two helix-hairpin-helix (HhH) motifs

Lineage:

1. Root: scop
2. Class: All alpha proteins
3. Fold: SAM domain-like
   4-5 helices; bundle of two orthogonally packed alpha-hairpins; involved in the interactions with DNA and proteins
4. Superfamily: RuvA domain 2-like
   duplication: contains two helix-hairpin-helix (HhH) motifs

Families:

1. DNA helicase RuvA subunit, middle domain (2)
2. NAD+-dependent DNA ligase, domain 3 (1)