红曲霉白色突变株因不产色素可扩大红曲霉的使用范围，对经紫外诱变后的红曲霉白色突变株（W1）进行固体发酵并对其所产生的酸性蛋白酶的性质进行初步研究。研究表明此酸性蛋白酶最适反应温度为50 ℃，在30~40 ℃下相对稳定；最适反应pH为3.0，在pH 3.0~5.0之间相对稳定；Mn2+、Ag+、K+对酸性蛋白酶有激活作用，Fe3+、Al3+、Mg2+、Cu2+对酸性蛋白酶有一定抑制作用。通过Sephadex-G75凝胶过滤层析及SDS-PAGE蛋白质电泳分析此蛋白酶的相对分子量范围大约在55000~60000之间。

The characteristics of acid protease produced by M. purpureus mutant W1 were preliminarily studied. The optimum reaction temperature and pH value of this acid protease were found to be 50 ℃ and 3.0, respectively. And the enzyme showed high stability within the temperature ranges of 30~40 ℃ and with the pH value of 3.0~5.0. It was also found that the activity of the protease could be inhibited by Fe3+, Al3+, Mg2+, and Cu2+, and activated by Mn2+, Ag+, and K+. The molecular weight of this protease was about 55000~60000 Da by Sephadex-G75 gel layer analysis and SDS-PAGE protein electrophoresis analysis.