This family of archaebacterial proteins are holliday junction resolvases (hjc gene) [1]. The Holliday junction is an essential intermediate of homologous recombination. This protein is the archaeal equivalent of RuvC but is not sequence similar.

1: A Holliday junction resolvase from Pyrococcus furiosus: functional similarity to Escherichia coli RuvC provides evidence for conserved mechanism of homologous recombination in Bacteria, Eukarya, and Archaea. Komori K, Sakae S, Shinagawa H, Morikawa K, Ishino Y; Proc Natl Acad Sci U S A 1999;96:8873-8878. PMID:10430863