[11] Aldehyde Oxidoreductases from Pyrococcus furiosus

An early study with Pyrococcus furiosus showed that growth of this hyperthermophilic archaeon is stimulated by the addition of tungsten to the medium. Subsequently, three distinct tungsten-containing enzymes were purified from this and related organisms. They are aldehyde ferredoxin oxidoreductase (AOR), which has been purifed from P. furiosus, Pyrococcus strain ES-4, and Thermococcus strain ES-1, formaldehyde ferredoxin oxidoreductase (FOR), which has been purified from Thermococcus litoralis and P. furiosus, 6 and glyceraldehyde-3-phosphate ferredoxin oxidoreductase (GAPOR), which has been obtained so far only from P. furiosus. All three enzymes catalyze the oxidation of various types of aldehyde using ferredoxin (Fd) as the physiological electron acceptor. This chapter describes the purification of AOR, FOR, and GAPOR from P. furiosus and summarizes some of their properties.