Didier R, Audic S, Robert C, Abergel C, Renesto P, Ogata H, La Scola B, Suzan M, Claverie JM. 2004. The 1.2-Megabase Genome Sequence of Mimivirus. Science 306:1344-1350.
This journal article summarizes the unique findings of the Mimivirus. It is one of the few viruses that have both type one and type two topoisomerases, DNA repair enzymes, and polysaccharide synthesis enzymes. The findings associated with this virus have highlighted the existence of a 4th domain of life. It is interesting because the large DNA virus had proofreading enzymes that are unique to this type of virus.
Having proofreading enzymes to cut out mutations in DNA is important for eukaryotes to be functional, but are often missing in viruses. Since the virus have such a large output of functioning proteins it would not be evolutionarily favorable to leave it unchecked from these unique proofreaders. If other virus genomes could be as stable as the Mimivirus it would make treating them simpler due to the lack of antigenic drift.