Cloning and functional expression of thermostable β-glucosidase gene from Thermoascus aurantiacus
Cloning and functional expression of thermostable β-glucosidase gene from Thermoascus aurantiacus
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DOI：
10.1007/s00253-006-0618-9
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发表时间：
2007-01-01
影响因子：
5
通讯作者：
Kumagai, Hidehiko
中科院分区：
文献类型：
--
作者：
Hong, Jiong;Tamaki, Hisanori;Kumagai, Hidehiko
从橙色嗜热菌IFO 9748中分离纯化了一种耐热β-葡萄糖苷酶（BGLI），并克隆了该酶的编码基因（bgl 1），在毕赤酵母（Pichia pastoris）中表达。推导的bgl 1编码的氨基酸序列与糖苷水解酶家族3的氨基酸序列高度相似。纯化重组酶并进行酶特性鉴定。重组BGLI在60 ℃孵育1小时后保留其初始活性的70%以上，并且在pH 3-8范围内稳定。酶的最适温度为70 ℃左右，最适pH为5左右。表达重组BGLI的巴斯德毕赤酵母能够利用纤维二糖作为碳源。
A thermostable beta-glucosidase (BGLI) was purified from Thermoascus aurantiacus IFO9748, and the gene (bgl1) encoding this enzyme was cloned and expressed in yeast Pichia pastoris. The deduced amino acid sequence encoded by bgl1 showed high similarity with the sequence of glycoside hydrolase family 3. The recombinant enzyme was purified and subjected to enzymatic characterization. Recombinant BGLI retained more than 70% of its initial activity after 1 h of incubation at 60 C and was stable in the pH range 3-8. The optimal temperature for enzyme activity was about 70 degrees C and the optimal pH was about 5. P. pastoris expressing recombinant BGLI became able to utilize cellobiose as a carbon source.