Sandia researcher examines assays for the screening of engineered enzymes, originally from the organism Sulfolobus solfataricus, which show increased activity and stability at acidic conditions and high temperatures. The original enzymes were found in a class of microorganisms known as ?extremophiles,? so named because of the extreme environmental conditions in which they live and thrive. The idea is that these organisms and their associated enzymes could somehow unlock the key to a new transportation economy based on a renewable biofuel, lignocellulosic ethanol.