Methanocaldococcus jannaschii was isolated from a submarine hydrothermal vent at Woods Hole Oceanographic Institution.
Surface material was collected at a "white smoker" chimney which revealed evidence of Methanocaldococcus jannaschii living in this extreme habitat of temperatures from 48 - 94 °C.
[6] Methanocaldoccus jannaschii is a member of the genus Methanocaldococcus (previously a part of Methanococcus) and is therefore sometimes referred to as a "class I" methanogen (e.g. [1]).
Methanocaldococcus jannaschii is a thermophilic methanogen, meaning it grows by making methane as a metabolic byproduct.
[citation needed] Many information processing pathways have also been studied in this organism, such as an archaeal-specific DNA polymerase family.