灰绿青霉阿魏酸酯酶的分离纯化和酶学性质研究

目的]研究青霉(Penicillium glaucum)XGY36胞外产阿魏酸酯酶的纯化和酶学性质。方法]菌株胞外产酶发酵液经硫酸铵沉淀、DEAE-cellulose DE52离子交换柱层析、Sephadex-G75分子筛层析进行纯化,得到纯度较高的酶蛋白,并对其酶学性质进行研究。结果]从菌株发酵液中分离纯化到电泳纯的阿魏酸酯酶,纯化倍数6.54,酶活性回收59.7%。阿魏酸酯酶经SDS-PAGE获得1个条带,其表观分子量为36.5 ku。催化底物阿魏酸乙酯的最适反应温度为50℃,最适p H为5.0。阿魏酸酯酶在60℃以下和p H 3.0~7.0范围内稳定。金属离子Zn~(2+)、Mg~(2+)、Ca~(2+)对酶有明显的激活作用,而Pb~(2+)、Hg~(2+)和Ag+对阿魏酸酯酶有强烈的抑制作用,Na+、K+、Mn~(2+)、Cu~(2+)和Fe~(2+)对酶活的影响不大。结论]青霉阿魏酸酯酶具有潜在的应用价值,适合应用于食品、医药及生物等领域。

Study on Separation,Purification and Enzymatic Properties of Ferulic Acid Esterase from Penicillium glaucum

Objective] The aim was to study purification and enzymatic properties of feruloyl esterase in the culture solution of Penicillium glau-cum XGY36.Method] The feruloyl esterase was obtained in the culture solution of Penicillium glaucum XGY36 and was purified to be homoge-neous by the steps of ammonium sulfate precipitation,DEAE-cellulose DE52 chromatographies,and Sephadex G-75 chromatography.The enzyme protein with high purity was obtained,enzymatic properties were studied.Result] Purification of about 6.54 fold was achieved with an overall yield of 59.7%.The molecular weight of purified feruloyl esterase was estimated to be about 36.5 ku by SDS-PAGE.The optimum temperature and pH of the enzyme activity were 50 ℃and 5.0,respectively in catalytic reaction of ethyl ferulate.The enzyme activity was stable under 60 ℃, and with pH range of 3.0-7.0.The activity of feruloyl esterase was highly enhanced by Zn2 +,Mg2 +and Ca2 +,whereas it was strongly inhibited by the metal ions Pb2 +,Hg2 +and Ag +,while Na +,K +,Mn2 +,Cu2 +and Fe2 +had no strong effect on feruloyl esterase activity.Conclusion] Fer-uloyl esterase has potential applied value and fit to apply in the fields of food,medicine and biology etc..