从分离自内蒙古柴达敏盐湖的嗜盐古菌中筛选高产胞外蛋白酶菌株，并对所产蛋白酶的酶学性质进行初步研究。结果表明，2株高产胞外蛋白酶嗜盐古菌CDM10和CDM12为新的分类单元。CDM10胞外蛋白酶最适反应条件为70～75 ℃，pH 8.0～9.0和1.5 mol/L NaCl。CDM12胞外蛋白酶最适反应条件为60～75 ℃，pH 7.0～9.0和1.5～2.5 mol/L NaCl。它们具有良好的热稳定性和盐度容忍性。抑制剂实验表明CDM10和CDM12的胞外蛋白酶是丝氨酸蛋白酶，半胱氨酸和金属离子对于蛋白酶活性的发挥具有重要的作用。

Haloarchaeal strains isolated from Chaidamin Salt Lake, Inner Mongolia were screened for high protease activity. Their enzyme properties were studied. The results showed that CDM10 and CDM12 displayed the highest protease activity, and represented novel taxa. The optimal protease activity of CDM10 occurred at 70-75 ℃, pH 8.0-9.0, and 1.5 mol/L NaCl. The CDM12 protease exhibited maximal activity at 60-75 ℃, pH 7.0-9.0, and 1.5-2.5 mol/L NaCl. The CDM10 and CDM12 proteases were highly stable over wide ranges of temperatures and NaCl concentrations. The inhibitor experiment suggested that the CDM10 and CDM12 proteases belonged to serine protease family, and the cysteine residues and metal ions were important for the enzyme activities.