摘要
采用PCR方法对短小芽孢杆菌A - 30菌株的耐碱性木聚糖酶基因进行克隆 .在木聚糖选择平板上用刚果红染色法筛选出阳性克隆 ,提取阳性克隆的重组质粒进行酶切鉴定和测序 .该基因在大肠杆菌中表达 ,过夜培养物胞外、胞内和周质空间的木聚糖酶酶活分别为 0 .15 9IUmL-1、0 .32 2IUmL-1和 0 .0 0 7IUmL-1.此木聚糖酶表现出较宽的pH作用范围 ,最适作用pH 7左右 ,在pH 9时仍有 6 0 %以上的酶活性 .图 4参
The alkali-tolerant xylanase gene of Bacillus pumilus A-30 was cloned by PCR. The positive clones were screened on the selected LB agar plates supplemented with 0.2% oat spelt xylan by Congo red staining method. The recombinant plasmid from one positive clone was used for further characterization and DNA sequencing. In Eschericia coli, the xylanase gene could be expressed by the recombinant plasmid and the activities in extracellular, intracellular and periplasmic fractions were 0.159 IU mL -1, 0.322 IU mL -1 and 0.007 IUmL -1 respectively. The xylanase had optimal activity at pH 7.0, and retained more than 60% of the activity even at pH 9.0. Fig 4, Ref 14
出处
《应用与环境生物学报》
CAS
CSCD
2001年第1期61-65,共5页
Chinese Journal of Applied and Environmental Biology
基金
国家自然科学基金资助项目! (No :39970 392 )
关键词
耐碱性木聚糖酶
基因克隆
表达
序列分析
短小芽孢杆菌
大肠杆菌
alkali-tolerant xylanase
gene cloning and expression
sequence analysis
Bacillus pumilus
Eschericia coli
