“…A number of proteases produced by hyperthermophilic archaea of the genera Desulfurococcus (Cowan et al, 1987), Sulfolobus (Fusek et al, 1990;, Pyrococcus (Eggen et al, 1990;Dib et al, 1998), Thermococcus (Klingeberg et al, 1995), Pyrobaculum (Völkl et al, 1994) and others have been described during past decades. Using the zymogram method (Tsiroulnikov et al, 2004), añ 120 kDa thermostable proteinase, active at 85 u C and pH 6.6 and 9.0 (data not shown), was found in the cell envelope fraction of strain 1221n T , grown on a-keratin.…”