摘要
从云南保山市的一眼温泉中分离到一株嗜热嗜酸菌,脂环酸芽孢杆菌Alicyclobacillus sp. A15。通过同源克隆和TAIL-PCR方法,从该菌株中克隆得到一个木聚糖酶基因xynA15,全长990 bp,编码329个氨基酸和一个终止密码子。将xynA15基因克隆到原核表达载体pET-22b(+)上,并转化至BL21(DE3),经过IPTG诱导,其表达产物具有木聚糖酶的活性。对其酶学性质研究发现,XynA15的最适温度为50℃,最适pH为7.0,不仅在较广的温度范围(35℃-60℃)内具有较高的酶活,而且在50℃具有较好的热稳定性。
Alicyclobacillus sp.A15 was isolated from the outflow of a hot spring in Baoshan City,Yunnan Province,China.xynA15 was cloned from the strain through homogolous cloning and TAIL-PCR,which consists of 990 bp and encodes 329 amino acids and one stop codon.Then it was inserted into the prokaryotic expression vector pET-22b(+) and transformed into Escherichia coli BL21(DE3).Xylanase activity was detected in the cultured supernantant after induced by isopropyl-β-d-1-thiogalactopyranoside(IPTG).The optimal temperature and pH was 50℃ and 7.0,respectively for XynA15 activity.XynA15 contains higher activity at 35-60℃ and better thermal stability at 50℃.
出处
《中国农业科技导报》
CAS
CSCD
2010年第6期114-119,共6页
Journal of Agricultural Science and Technology
基金
国家转基因生物新品种培育重大专项(2008ZX003-002)
国家肉鸡产业技术体系(nycytx-42-G2-05)资助