Comparison of Biochemical Properties of Recombinant and Native Phanerochaete flavido-alba Laccases  

出　　处：《Journal of Agricultural Science and Technology(B)》2013年第11期776-782,共7页农业科学与技术（B）

摘　　要：Laccases are blue copper oxidases （E.C. 1.10.3.2 benzenediol：oxygen oxidoreductase） that catalyze the one-electron oxidation of phenolics, aromatic amines and other electron-rich substrates with the concomitant reduction of 02 to H20. They are currently seen as highly interesting industrial enzymes because of their broad substrate specificity. The Phanerochaete flavido-alba laccase is expressed and secreted as a soluble active enzyme by Aspergillus niger （rLac-LPFA）. rLac-LPFA is easily purified to homogeneity. Metal ions like HgCI2, KC12, FeSO4 and MgSO4 at a concentration of 2 mM have inhibiting effect on recombinant and native laccase, whereas, CuSO4 and MnSO4 moderately increase both enzyme activities. Two potential inhibitors （sodium azide and EDTA） inhibited enzyme activity, whereas, urea and SDS have no effect on enzyme activity. The Km and V,,ax values for recombinant laccase are 0.65 mM and 300 U/mg respectively for 2,6-DMP as substrate.

关 键 词：Recombinant laccase Phanerochaeteflavido-alba kinetics constants metal ions inhibitors. 

分 类 号：TQ138.11[化学工程—无机化工] TS745[轻工技术与工程—制浆造纸工程]