The RadA Recombinase and Paralogs of the Hyperthermophilic Archaeon Sulfolobus solfataricus.

Repair of DNA double-strand breaks is a critical function shared by organisms in all three domains of life. The majority of mechanistic understanding of this process has come from characterization of bacterial and eukaryotic proteins, while significantly less is known about analogous activities in the third, archaeal domain. Despite the physical resemblance of archaea to bacteria, archaeal proteins involved in break repair are remarkably similar to those used by eukaryotes. Investigating the function of the archaeal version of these proteins is, in many cases, simpler than working with eukaryotic homologs owing to their robust nature and ease of purification. In this chapter, we describe methods for purification and activity analysis for the RadA recombinase and its paralogs from the hyperthermophilic acidophilic archaeon Sulfolobus solfataricus.