The process of replication in archaea has a number of features in common with replication in eukaryotic cells. Many of the proteins taking part are more similar to those in eukaryotic cells than to those in eubacteria. Like eubacteria, some archaea have a single origin of replication, but the archaean Sulfolobus solfataricus has two origins of replication, similar to the multiple origins seen in eukaryotic genomes. The origins of archaea do not contain the typical sequences recognized by bacterial initiator proteins; instead, they have sequences that are similar to those found in eukaryotic origins. The initiator proteins of archaea are also more similar to those of eukaryotes than to those of eubacteria. These similarities in replication between archaeal and eukaryotic cells reinforce the conclusion that the archaea are more closely related to eukaryotic cells than to the prokaryotic eubacteria.