作　　者： ; ; ; ; ;

机构地区： 湖南大学环境科学与工程学院

出　　处： 《环境科学》 2012年第9期3220-3227,共8页

摘　　要： 从农业固体废物堆肥中分离得到1株高产漆酶的新菌株,通过对其形态特征和ITS序列分析,鉴定该菌株为哈茨木霉(Hypocrea lixii).以Cu1AF和Cu2R为引物对该菌株的漆酶基因进行扩增,PCR产物回收克隆后测序得到长度为148 bp的漆酶基因片段.在液体培养条件下,菌株漆酶活力可达到67.5 U.mL-1.对该菌株的漆酶酶学性质初步研究显示:漆酶相对分子质量大约为60×103,酶反应的最适温度为35℃,最适pH为4.0;在60℃时漆酶半衰期>1 h;漆酶氧化2,2'-联氮双(3-乙基苯并噻唑啉-6-磺酸)二铵盐(ABTS)的米氏常数(Km)值为1.00 mmol.L-1;金属离子对酶活的影响很大,Na+、Fe2+、Fe3+、Pb2+、Zn2+对酶活都有抑制作用.该菌株有很好的应用潜力来作农业废物堆肥处理系统的强化菌剂. A new fungal strain with high laccase production was isolated from the agricultural waste composting.It was identified as Hypocrea lixii based on morphological analysis and ITS sequence.The partial laccase gene of the new strain was successfully amplified using the primer pair Cu1AF and Cu2R.After purification and cloning of the PCR product,a 148 bp fragment of laccase gene was obtained.The laccase activity of the strain reached a peak value of 67.5 U·mL^-1 in liquid medium.The molecular mass of the purified laccase was determined to be about 60×10^3.The optimum temperature and pH for enzyme activity were 35℃ and 4.0,respectively.The half-time of the enzyme was more than 1 h at 60℃.Under standard assay conditions,Km values was 1.00 mmol·L^-1 towards ABTS.Laccase activity was inhibited by several metal ions,such as Na＋,Fe^2＋,Fe^3＋,Pb^2＋and Zn^2＋.This strain has a good potential for application as a bioaugmentation strain in the agricultural waste composting system.

关 键 词： 堆肥 漆酶 木霉 漆酶基因 酶学性质

领　　域： [环境科学与工程]