A thermotolerant β-glucosidase isolated from an endophytic fungi, Periconia sp., with a possible use for biomass conversion to sugars
A thermotolerant β-glucosidase isolated from an endophytic fungi, Periconia sp., with a possible use for biomass conversion to sugars
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DOI：
10.1016/j.pep.2008.05.022
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发表时间：
2009-10-01
影响因子：
1.6
通讯作者：
Eurwilaichitr, Lily
中科院分区：
文献类型：
--
作者：
Harnpicharnchai, Piyanun;Champreda, Verawat;Eurwilaichitr, Lily
一种真菌菌株，BCC 2871（Periconia sp.），发现产生耐热β-葡糖苷酶，BGLI，具有在生物质转化中应用的高潜力。目的酶基因经鉴定后克隆到毕赤酵母KM 71中。与BCC 2871产生的天然酶类似，重组b-葡萄糖苷酶显示最适温度为70 ° C，最适pH为5和6。即使在高温下长时间孵育后，该酶仍继续表现出高活性，在70 ℃下孵育1.5 h后，仍保持最大活性的近60%。它在碱性条件下也是稳定的，在pH >= 8孵育2小时后几乎保留100%的最大活性。该酶对纤维二糖和其他含有糖基的合成底物具有高活性，以及对羧甲基纤维素具有纤维素活性。在纤维二糖、葡萄糖和蔗糖存在下，酶的热稳定性显著提高。该β-葡萄糖苷酶能够将稻草水解成单糖。将该β-葡糖苷酶加入到含有商业纤维素酶Celluclast（R）1.5L（Novozyme，丹麦）的稻草水解反应中，与没有β-葡糖苷酶的水解相比，导致释放的还原糖增加。这种酶是将木质纤维素生物质转化为生物燃料和化学品的应用的候选者。(C)2008年爱思唯尔公司All rights reserved.
A fungal strain, BCC2871 (Periconia sp.), was found to produce a thermotolerant beta-glucosidase, BGLI, with high potential for application in biomass conversion. The full-length gene encoding the target enzyme was identified and cloned into Pichia pastoris KM71. Similar to the native enzyme produced by BCC2871, the recombinant b-glucosidase showed optimal temperature at 70 degrees C and optimal pH of 5 and 6. The enzyme continued to exhibit high activity even after long incubation at high temperature, retaining almost 60% of maximal activity after 1.5 h at 70 degrees C. It was also stable under basic conditions, retaining almost 100% of maximal activity after incubation for 2 h at pH >= 8. The enzyme has high activity towards cellobiose and other synthetic substrates containing glycosyl groups as well as cellulosic activity toward carboxymethylcellulose. Thermostability of the enzyme was improved remarkably in the presence of cellobiose, glucose, or sucrose. This beta-glucosidase was able to hydrolyze rice straw into simple sugars. The addition of this beta-glucosidase to the rice straw hydrolysis reaction containing a commercial cellulase, Celluclast (R) 1.5L (Novozyme, Denmark) resulted in increase of reducing sugars being released compared to the hydrolysis without the beta-glucosidase. This enzyme is a candidate for applications that convert lignocellulosic biomass to biofuels and chemicals. (C) 2008 Elsevier Inc. All rights reserved.