云芝(Coriolus versicolor)木质素过氧化物酶(LiP)酶学性质分析

Enzymological Characteristics of Lignin Peroxidase (LiP) from Coriolus versicolor

研究云芝(Coriolus versicolor)产木质素过氧化物酶(Lip)酶活力随时间的变化情况,以及温度、pH值、金属离子及化合物对云芝LiP酶活力和稳定性的影响,对该酶底物浓度效应和Km值进行测定。结果表明:云芝培养12d,其酶活力最高,为72U/mL。该酶的最适温度为40℃,在30～40℃范围内稳定;最适pH值为2.5,pH值在2.0～3.5较稳定;Zn2+对LiP有激活作用,Na+对酶活力没有影响,Ca2+、K+、Mg2+、Mn2+、Cu2+及EDTA、SDS、β-巯基乙醇都表现出抑制作用;Km值为2.05×10-4mol/L。

In this paper,the enzymological characteristics of lignin peroxidase （LiP） from C.versicolor were investigated.The effects of temperature,pH,metal ions and compounds on the activity and stability of the enzyme were explored.Meanwhile,the relationship between substrate concentration and LiP activity was also studied,and the enzyme was measured for its Km.The highest enzyme activity was 72 U/mL when C.versicolor was cultured for up to 12 days.The optimal temperature and pH of the enzyme were 40 ℃ and 2.5,respectively.It exhibited a good stability in a range from 30 to 40 ℃ for temperature and from 2.0 to 3.5 for pH.Its activity could be activated by Zn^2＋ and inhibited by Ca^2＋,K^＋,Mg^2＋,Mn^2＋,Cu^2＋,EDTA,SDS and β-mercaptoethanol,while Na＋ had no effect on its activity.The Km of the enzyme was 2.05 × 10^-4 mol/L.