The tree of life shows the relationship between all organisms based on their common ancestry. Until 1977, it comprised two major branches: Prokaryotes and eukaryotes. Work by Carl Woese and other microbiologists led to the recategorization of prokaryotes and the proposal of three primary domains: Eukarya, Bacteria and Archaea. Microbiological, genetic and biochemical techniques were then needed to study the third domain of life. Haloferax volcanii, a halophilic species belonging to the phylum Euryarchaeota, has provided many useful tools to study Archaea, including easy culturing methods, genetic manipulation and phenotypic screening. This review will focus on DNA replication and DNA repair pathways in H. volcanii, how this work has advanced our knowledge of archaeal cellular biology, and how it may deepen our understanding of bacterial and eukaryotic processes

Work in the T.A. laboratory has been supported by the Bio technology and Biological Sciences Research Council (BBSRC) (grant numbers BB/N016491/1 and BB/R007543/1 to P.P.-A. and A.D., respectively). The funders had no role in study design, data col lection and interpretation, nor the decision to submit the work for publication