Nanoarchaeum equitans

Ignicoccus hospitalis with attached Nanoarchaeum equitans

Nanoarchaeum equitans is a 400 -nm single-celled organisms from the group of archaea that lives symbiotically or parasitically on other archaea. The microorganism was discovered at the University of Regensburg in 2002 in the laboratory of Karl O. Stetter. The genome was fully sequenced before 17 months later. So far Nanoarchaeum equitans is the only known representative of the department " Nanoarchaeota ", but it has been described so far not formally valid, therefore all systematic names in quotation marks.

The name Nanoarchaeum equitans ( " the horse Urzwerg " ) received the organism because of its small size and because it attaches itself to other Archaea. Whether it is a symbiosis or parasitism is unknown as yet. One advantage for the host Ignicoccus hospitalis We have not yet discovered.

The genome of Nanoarchaeum equitans is very small with only 490 kilobase pairs. It is the smallest so far described the genome of a microorganism, and at the same time one of the most compact. 95 percent of the genome coding for proteins or RNAs, the proportion of non-functioning genes ( " pseudogenes " ) is therefore low. However Nanoarchaeum equitans is not able to produce all materials needed for life itself and is therefore dependent on a host organism.

Nanoarchaeum equitans is an extremophile organism, it can exist only under hot 70-110 ° C., sulphurous, oxygen-free conditions that prevailed on Earth some 3.8 billion years ago. Today such an environment exists for example, in deep-sea hydrothermal vents to as black smokers.