木糖异构酶
异构酶
嗜热菌
生物化学
木糖
枯草芽孢杆菌
生物
大肠杆菌
酶
分子克隆
氨基酸
基因
化学
肽序列
细菌
遗传学
发酵
作者
Wu‐Xiang Liao,Linda Earnest,Siew Ling Kok,Kandiah Jeyaseelan
出处
期刊:PubMed
日期:1995-06-01
卷期号:36 (2): 401-10
被引量:7
摘要
The gene (xylA) encoding a thermostable xylose isomerase has been isolated and characterized from a thermophilic Bacillus species for the first time. The xylA open reading frame of 1323 bp encoded a protein containing 441 amino acids with a calculated molecular weight of 50,176. The amino acid sequence of this protein showed 76% homology to xylose isomerase isolated from Bacillus subtilis and contained all the important catalytic domains of the enzyme. The gene complemented the xyl-5 mutation and produced a functional enzyme constitutively in Escherichia coli. The crude cell-free extract of E. coli recombinants exhibited xylose isomerase activity over a wide range of temperatures from 60 to 100 degrees C with an optimal enzyme activity of 10.4 Units/mg protein at 85 degrees C. This optimal temperature was one of the highest reported so far for thermostable xylose isomerases. The recombinant enzyme was found to be a tetramer with each subunit having molecular weight of 50,000.
科研通智能强力驱动
Strongly Powered by AbleSci AI