摘要
从木质素降解菌Phanerochaetechrysosporium中纯化出两种木质素降解酶:木质素过氧化物酶(LiP)和锰依赖过氧化物酶(MnP)。经测定LiP和MnP的分子量分别为37kD和40kD,最适作用温度均是37℃;保温2h,LiP的半失活温度为40℃,MnP为45℃;LiP最适作用pH2.8,稳定pH2.2～5.2;MnP最适作用pH4.6,稳定pH4.0～7.0。Fe2+对LiP和MnP均表现出促进作用,Na+、K+、Ca2+、Mg2+、Zn2+、Fe3+、Ag+、Co2+、NH4+对LiP有促进作用,对MnP则表现出抑制作用。与此相反,Mn2+对MnP酶活的高效促进作用,对LiP表现出了轻度的抑制作用,这也体现出了MnP对Mn2+的依赖性。Cu2+对LiP活性无影响,而对MnP有强烈的抑制作用。Fe3+对两者活性的抑制都达到了90%。
The wood-destroying fungus Phanerochaete chrysosporium secretes extracellular enzymes known as lignin peroxidases that are in- volved in the biodegradation of lignin and a number of environmental pollutants. Several lignin peroxidases are produced in liquid cultures of this fungus. Here two lignin degradation enzymes, lignin peroxidase （LiP） and manganese peroxidase （MnP） were purified and characterized from Phanerochaete chrysosporium culture. The molecular weight of LiP and MnP are 37 KD and 40 KD respectively. Both of them have the same optimized activity temperature of 37 ℃. The temperature for losing half of the activity （t1/2） within 2 h is 40 ℃ for LiP and 45 ℃ for MnP. The optimum pH of MnP and LiP are 4.6 and 2.8 respectively. MnP is relatively stable in pH 4.0-7.0 and LiP in 2.2-5.2. Fe^2＋ promotes the activity of both LiP and MnP, Na^＋,K^＋,Ca^2＋,Mg^2＋,Zn^3＋,Fe^＋,Ag＋,Co^2＋,NH4^＋ promote the activity of LiP but inhibit that of MnP. Cu^2＋ shows strong inhibition only to MnP but has no effect on LiP.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2007年第1期295-300,共6页
Journal of Agro-Environment Science
基金
国家自然科学基金项目(30170030)
关键词
木质素过氧化物酶
锰依赖过氧化物酶
黄孢原毛平革菌
酶的纯化
酶学特性
lignin peroxidase （LiP）
manganese peroxidase （MnP）
Phanerochaete chrysosporium
enzyme purification
enzyme properties
