Cheng Shujie, Yang Peizhou, Guo Liqiong, Lin Junfang, Lou Nannan
Department of Bioengineering, College of Food Science, South China Agricultural University, Tianhe, Guangzhou, China.
Bioresour Technol. 2009 Oct;100(19):4475-80. doi: 10.1016/j.biortech.2009.04.021. Epub 2009 May 12.
Multi-functional cellulase gene mfc was expressed in Coprinus cinereus under naturally non-inductive conditions using three heterologous promoters. Endo-beta-1,4-glucanase expression was achieved in solid and liquid media with promoter sequences from the Lentinula edodesgpd gene, the Flammulina velutipes gpd gene and the Volvariella volvaceagpd gene. As measured by enzyme activity in liquid cultures, a 613-bp gpd promoter fragment from L. edodes was most efficient, followed by a 752-bp gpd fragment from F. velutipes. The V. volvacea gpd promoter sequence was less active, in comparison. Irrespective of the promoter used, enzymatic activities increase 34-fold for highly active transformants and 29-fold for less active one by using cellulase-inducing medium. The highest activities of endo-beta-1,4-glucanase (34.234 U/ml) and endo-beta-1,4-xylanase (263.695 U/ml) were reached by using the L. edodesgpd promoter.
利用三种异源启动子,在自然非诱导条件下,在灰盖鬼伞中表达多功能纤维素酶基因mfc。使用香菇gpd基因、金针菇gpd基因和草菇gpd基因的启动子序列,在固体和液体培养基中实现了内切-β-1,4-葡聚糖酶的表达。通过液体培养中的酶活性测定,香菇的一个613 bp的gpd启动子片段效率最高,其次是金针菇的一个752 bp的gpd片段。相比之下,草菇gpd启动子序列的活性较低。无论使用哪种启动子,通过使用纤维素酶诱导培养基,高活性转化体的酶活性增加34倍,低活性转化体的酶活性增加29倍。使用香菇gpd启动子,内切-β-1,4-葡聚糖酶(34.234 U/ml)和内切-β-1,4-木聚糖酶(263.695 U/ml)达到最高活性。