摘要
研究了发酵性丝孢酵母所产蛋白酶的最适作用条件及稳定性。结果表明,发酵性丝孢酵母蛋白酶的最适反应温度为55℃,最适反应p H为7.0;有良好的热稳定性,50℃保温30 min,仍保留78%以上的酶活力;贮存稳定性也较好,10℃贮存60 h,仍保留80%左右的酶活力;5 mmol/L的金属离子Mn2+和Ca2+对蛋白酶有激活作用,其中Ca2+激活作用最显著,使酶活提高了0.87倍;1%(w/w)的表面活性剂吐温-100可以促进酶活力,使酶活提高了24.6%,1%(w/w)的SDS对酶活力有抑制作用,将残余酶活降低为原酶液的67.1%;2.5%(w/w)的葡萄糖、半乳糖和海藻糖等能抑制该蛋白酶活力,其中海藻糖抑制作用最显著,使残余蛋白酶活力降低到原酶液的23.6%;甘油可作为酶保护剂保护蛋白酶稳定性,且浓度为7.5%(w/w)的甘油能明显激活酶活力。
The optimum conditions and stabilities of protease produced by Trichosporonfermentans were investigated. The results indicated that the optimum temperature and pH of the protease was 55 ℃ and 7.0 respectively. The protease exhibited its excellent thermal stability, its enzyme activity remained above 78% at 50 ℃ for 20 min. The protease also showed its better storage stability, the residual enzyme activity was about 80% if it was preserved at 10 ℃ for 60 h. Metal ions such as Mn2＋ and Ca2＋ of 5 mmol/L could activate the protease, and Ca2＋ increased markedly by 87% of the enzyme activity. Surfactant Tween-100 of 1% （w/w） increased the protease activity by 24.6%, while SDS of 1% （w/w） inhibited the protease activity to 67.1%. Glucose, galactose and trehalose of 2.5% （w/w） could inhibit the protease, and trehalose had the most significant inhibition on protease, decreasing the enzyme activity to 23.6%. Glycerol protected protease stability effectively, and glycerol at the concentration of 7.5% （w/w） had an obviously active effect on protease activity.
出处
《工业微生物》
CAS
CSCD
2015年第4期46-50,共5页
Industrial Microbiology
