Synergistic hydrolysis of xylan using novel xylanases, β-xylosidases, and an α-L-arabinofuranosidase from Geobacillus thermodenitrificans NG80-2
Synergistic hydrolysis of xylan using novel xylanases, β-xylosidases, and an α-L-arabinofuranosidase from Geobacillus thermodenitrificans NG80-2
复制标题
使用来自热脱氮地芽孢杆菌 NG80-2 的新型木聚糖酶、β-木糖苷酶和 α-L-阿拉伯呋喃糖苷酶协同水解木聚糖
DOI：
10.1007/s00253-017-8341-2
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发表时间：
2017-08-01
影响因子：
5
通讯作者：
Feng, Lu
中科院分区：
文献类型：
--
作者：
Huang, Di;Liu, Jia;Feng, Lu
来自各种类型木材的木质纤维素生物质已成为生产生物燃料和生物基化学品的可再生资源。木聚糖是木材半纤维素的主要成分，高效酶促木聚糖水解可以提高木质纤维素生物质的利用率。本研究从嗜热原油降解菌Geobacillustthermorecyclificans NG 80 -2中鉴定出一个木聚糖降解基因簇。参与木聚糖水解的酶包括两种木聚糖酶（XynA 1、XynA 2）、三种β-木聚糖酶（XynB 1、XynB 2、XynB 3）和一种α-l-阿拉伯呋喃糖苷酶（AbfA），其具有许多独特的特征，例如高pH耐受性、高热稳定性和宽底物范围。这三种β-木糖醇酶对抑制副产物（木糖）积累具有高度抗性。此外，木聚糖酶、β-木糖苷酶和α-l-阿拉伯呋喃糖苷酶的组合对木聚糖降解表现出最大的协同作用（XynA 2、XynB 1和AbfA对燕麦斯佩耳特小麦或山毛榉木聚糖; XynA 2、XynB 3和AbfA对桦木木聚糖）。我们已经证明，所提出的酶混合物几乎完全将复杂的木聚糖转化为木糖和阿拉伯呋喃糖，并且具有将植物生物质转化为生物燃料和生物化学品的巨大潜力。
Lignocellulosic biomass from various types of wood has become a renewable resource for production of biofuels and biobased chemicals. Because xylan is the major component of wood hemicelluloses, highly efficient enzymes to enhance xylan hydrolysis can improve the use of lignocellulosic biomass. In this study, a xylanolytic gene cluster was identified from the crude oil-degrading thermophilic strain Geobacillus thermodenitrificans NG80-2. The enzymes involved in xylan hydrolysis, which include two xylanases (XynA1, XynA2), three beta-xylosidases (XynB1, XynB2, XynB3), and one alpha-l-arabinofuranosidase (AbfA), have many unique features, such as high pH tolerance, high thermostability, and a broad substrate range. The three beta-xylosidases were highly resistant to inhibition by product (xylose) accumulation. Moreover, the combination of xylanase, beta-xylosidase, and alpha-l-arabinofuranosidase exhibited the largest synergistic action on xylan degradation (XynA2, XynB1, and AbfA on oat spelt or beechwood xylan; XynA2, XynB3, and AbfA on birchwood xylan). We have demonstrated that the proposed enzymatic cocktail almost completely converts complex xylan to xylose and arabinofuranose and has great potential for use in the conversion of plant biomass into biofuels and biochemicals.