General Information: Sulfolobus islandicus L.S.2.15 (Lassen #1) was isolated from Lassen National Park in California, USA. Hyperthermophilic acidophilic sulfur-metabolizing archeon. Sulfolobus islandicus is a thermo-acidophilic archeae commonly identified in hot, acidic sulfur springs. This organism can grow both chemoautotrophically, using sulfur or hydrogen sulfide, and heterotrophically. S. islandicus can play host to a number of plasmids and viruses which may be useful in developing tools for genetic analysis. In addition, Sulfolobus islandicus isolates from different areas in Russia, Iceland, and the United States have been shown to be genetically distinct from each other making this organism useful for comparative analysis.