State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, China.
J Biosci Bioeng. 2012 Jun;113(6):697-703. doi: 10.1016/j.jbiosc.2012.01.016. Epub 2012 Mar 3.
The Trametes sp. AH28-2 laccase gene lacA fused to cellobiohydrolase I signal peptide coding sequence was heterologously expressed in T. reesei. The lacA cDNA was under the control of the Aspergillus nidulans glyceraldehyde-3-phosphate dehydrogenase promoter. Native PAGE analysis indicated that two transformants, L8 and L38, were able to secrete recombinant laccase A, and their laccase activities corresponding to ABTS oxidation reached 3.62 IUml(-1) and 1.50 IUml(-1) respectively. Most of the characteristics of the recombinant laccase were similar to those of the native enzyme. Reducing sugar yields of L8 and L38 obtained from saccharification of corn residue by crude enzyme increased by 31.3% and 71.6% respectively compared to the host strain. These results indicated that the engineering strains developed in this work could be potentially used for laccase production and tailoring cellulase properties with laccase proteins through genetic manipulation would be a feasible strategy to improve saccharification efficiency of biomass by cellulase preparation.
担子菌 AH28-2 漆酶基因 lacA 与纤维二糖水解酶 I 信号肽编码序列融合，在里氏木霉中异源表达。lacA cDNA 受构巢曲霉 3-磷酸甘油醛脱氢酶启动子的控制。天然聚丙烯酰胺凝胶电泳分析表明，两个转化子 L8 和 L38 能够分泌重组漆酶 A，其 ABTS 氧化的漆酶活性分别达到 3.62IUml(-1)和 1.50IUml(-1)。重组漆酶的大多数特性与天然酶相似。与出发菌株相比，用粗酶液对玉米秸秆进行糖化后，L8 和 L38 获得的还原糖产率分别提高了 31.3%和 71.6%。这些结果表明，本研究中开发的工程菌可用于漆酶的生产，通过遗传操作修饰漆酶蛋白来改变纤维素酶的性质可能是提高纤维素酶制剂生物量糖化效率的一种可行策略。
