Bacterial mode of replication with eukaryotic-like machinery in a hyperthermophilic archaeon

Despite a rapid increase in the amount of available archaeal sequence infor mation, little is known about the duplication of genetic material in the th ird domain of life. We identified a single origin of bidirectional replicat ion in Pyrococcus abyssi by means of in silico analyses of cumulative oligo mer skew and the identification of an early replicating chromosomal segment . The replication origin in three Pyrococcus species was found to be highly conserved, and several eukaryotic-like DNA replication genes were clustere d around it. As in Bacteria, the chromosomal region containing the replicat ion terminus was a hot spot of genome shuffling. Thus, although bacterial a nd archaeal replication proteins differ profoundly, they are used to replic ate chromosomes in a similar manner in both prokaryotic domains.