【摘要】 为得到特殊性质的脂肪酶酶种 ,从来源于极端环境的 2 7份样品中定向筛选脂肪酶产生菌 ,并构建了一个小型的菌种库。其中酵母L112在 2 0℃ ,pH5 .0时酶活为 18.6u ml,属低温酸性酶种。酶学性质研究表明 ,该酶最适作用温度为 2 5～ 30℃ ,最适pH为 5 .4。在pH4 .8,5 0℃条件下 4 0min保持 6 0 %以上酶活。Mg2 + 和Ca2 + 对酶有激活作用 ,Zn2 + 、Fe2 + 、Cu2 + 和EDTA有抑制作用。该产酶菌株经中国科学院微生物研究所鉴定为罗伦隐球酵母 (Cryptococcuslaurentii(Kufferath)C .E .Skinner)。更多还原

【Abstract】 For obtaining lipase of special quality,lipase-producing strains were directional screened from 27 samples which collected from extreme environments. Various strains constructed a library of lipase-proudcing strains.Among them,yeast L112’s lipase activity could reach 18.6u/ml at 20℃ and pH 5.0.As a reasult the characteristic of acid lipase was studied in this essay.The lipase activity could reach the highest at pH5.4 and 25～30℃,and survival 60% below 50℃ for 40min at pH4.8.Different metal ions showed adverse effects on the lipase activity.Mg²⁺ and Ca²⁺ enhanced the lipase activity,whereas Zn²⁺,Fe²⁺,Cu²⁺ and EDTA cause inhibition.The lipase-proudcing strain was certificated as Cryptococcus laurentii（Kufferath） C.E. Skinner by Institute of Microbiology,Acadmy of Sciences,Beijing,China.更多还原