Extremophiles and their adaptation to hot environments

Water-containing terrestrial, subterranean and submarine high temperature a reas harbor a variety of hyperthermophilic bacteria and archaea which are a ble to grow optimally above 80 degrees C. Hyperthermophiles are adapted to hot environments by their physiological and nutritional requirements. As a consequence, cell components like proteins, nucleic acids and membranes hav e to be stable and even function best at temperatures around 100 degrees C. The chemolithoautotrophic archaeon Pyrolobus fumarii is able to grow at 11 3 degrees C and, therefore, represents the upper temperature border of life . For the first time, (vegetative) cultures of Pyrolobus and Pyrodictium ar e able to survive autoclaving. (C) 1999 Federation of European Biochemical Societies.