食品科学

• 生物工程 • 上一篇    下一篇

枯草芽孢杆菌木聚糖酶的克隆表达及其酶解两种木聚糖的产物分析

韦露莎,吴一飞,陈 辉*   

  1. 西北农林科技大学林学院,陕西 杨凌 712100
  • 出版日期:2016-03-15 发布日期:2016-03-17

Cloning and Expression of Bacillus subtilis Xylanase and Determination of Hydrolysis Products of Two Different Xylans by It

WEI Lusha, WU Yifei, CHEN Hui*   

  1. College of Forestry, Northwest A&F University, Yangling 712100, China
  • Online:2016-03-15 Published:2016-03-17

摘要:

通过基因克隆方法获得枯草芽孢杆菌木聚糖酶XynA,考察经镍离子亲和柱纯化后的XynA分别在桦木木聚糖和毛榉木木聚糖中的酶解情况,利用薄层色谱法(thin layer chromatography,TLC)及基质辅助激光解吸/电离飞行时间质谱(matrix-assisted laser desorption/ ionization time-of-flight mass spectrometry,MALDI-TOF/MS)法鉴定木聚糖酶XynA的酶解产物。运用MALDI-TOF/MS分析枯草芽孢杆菌木聚糖酶XynA酶解桦木木聚糖和毛榉木木聚糖产物不同的聚合度寡糖的分布情况。结果表明:在桦木木聚糖酶解液中,产生的中性木寡糖主要为木二糖(X2)和木三糖(X3),酸性木寡糖聚合度为4~12,并且每一个酸性木寡糖上仅连接着一个甲基葡萄糖醛酸侧链(MeG)。在毛榉木木聚糖酶解液中,产生的中性木寡糖与在桦木木聚糖酶解液中相同,酸性木寡糖的结构相似,聚合度为4~16。因此木聚糖酶XynA具有生产木二糖(X2)和木三糖(X3)以及酸性木寡糖(MeGXn)的功能。

关键词: 木聚糖内切酶, 低聚木糖, 基质辅助激光解吸/电离飞行时间质谱

Abstract:

Matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF/MS) was applied
to analyze molecular weight distribution of hydrolysis products from birchwood xylan and beechwood xylan digested
by Bacillus subtilis xylanase (XynA), obtained through recombinant expression and purified by Ni+-IDA column
chromatography. The hydrolysis products were identified by thin layer chromatography (TLC) and MALDI-TOF/MS.
Results showed the enzymatic hydrolysis of birchwood xylan yielded mainly xylobiose (X2) and xylotriose (X3) as well as
acidic xylooligosacchrides with a degree of polymerization (DP) of 4–12 each including a single methyl-glucuronic acid side
chain. Both xylobiose and xylotriose were found in the hydrolysate of beechwood xylan as well as acidic xylooligosacchrides
with a DP of 4–16 structurally similar to those from birchwood xylan. Therefore, the recombinant XynA has the potential to
produce X2, X3 and acidic xylooligosacchrides.

Key words: xylanase, xylooligosaccrides, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF/MS)

中图分类号: