生物技术通报2015，Vol.31Issue(5)：186-193,8.DOI:10.13560/j.cnki.biotech.bull.1985.2015.05.029
来源于瘤胃厌氧真菌Neocallimastix frontalis木聚糖酶在毕赤酵母中的表达
Expression of a Xylanase Gene Originated from Rumen Anaerobic FungiNeocallimastix frontalis inPichia pastoris
摘要
Abstract
The anaerobic fungus Neocallimastix frontalisis one of main microorganisms in the rumen degrading xylan and cellulose and its xylanase has the potential application value. In this study, a xylanase gene Xyn11B originated from N. frontaliswas codon optimized, and the optimized gene Xyn11Bm was synthesized. Based on the gene engineering technology, the yeast expression vector pPIC9K-Xyn11Bm was constructed, and the xylanase was induced and expressed in Pichia pastoris GS115. In shake flask level, enzyme activity of the recombinant Xyn11Bm reached the maximum up to 4874.8 U/mL. In 10 L fermentor, at 96 h after induction, the activity of recombinant enzyme was 5139.7 U/mL, cell wet weight and dry weight were 216.7 g/L and 117.3 g/L. Enzymatic properties analysis showed that the optimum reaction temperature and pH of Xyn11Bm were 50℃ and 5.0. In pH5.0-8.0, the enzyme had sound stability, but poor temperature stability. Substrate specificity analysis showed that recombinant Xyn11Bm could hydrolyze oat spelt xylan, birch xylan and soluble xylan 4-O-Me-D-glucurono-D-xylan, but not degrade lichenin and barley β-glucan. This indicated that the recombinant Xyn11Bm had potential application value.关键词
Neocallimastixfrontalis/木聚糖酶/毕赤酵母/密码子优化/酶学性质Key words
Neocallimastix frontalis/xylanase/Pichia pastoris/codon optimization/enzymatic properties引用本文复制引用
汪艳,李晓,陈勇,武运..来源于瘤胃厌氧真菌Neocallimastix frontalis木聚糖酶在毕赤酵母中的表达[J].生物技术通报,2015,31(5):186-193,8.基金项目
新疆维吾尔自治区高技术研究发展项目(201211104),新疆研究生科研创新项目(XJGRI2013112) （201211104）
