A new xylanase from thermoacidophilic Alicyclobacillus sp A4 with broad-range pH activity and pH stability

作者：Bai, Yingguo; Wang, Jianshe; Zhang, Zhifang; Yang, Peilong; Shi, Pengjun; Luo, Huiying; Meng, Kun; Huang, Huoqing; Yao, Bin^*

来源：Journal of Industrial Microbiology and Biotechnology, 2010, 37(2): 187-194.

DOI：10.1007/s10295-009-0662-4

• Alicyclobacillus sp.
• pH adaptability
• pH stability
• Thermoacidophilic strain
• Xylanase

We have identified a highly pH-adaptable and stable xylanase (XynA4) from the thermoacidophilic Alicyclobacillus sp. A4, a strain that was isolated from a hot spring in Yunnan Province, China. The gene (xynA4) that encodes this xylanase was cloned, sequenced, and expressed in Escherichia coli. It encodes a 338-residue polypeptide with a calculated molecular mass of 42.5 kDa. The deduced amino acid sequence is most similar to (53% identity) an endo-1,4-beta-xylanase from Geobacillus stearothermophilus that belongs to family 10 of the glycoside hydrolases. Purified recombinant XynA4 exhibited maximum activity at 55A degrees C and pH 7.0, had broad pH adaptability (> 40% activity at pH 3.8-9.4) and stability (retaining > 80% activity after incubation at pH 2.6-12.0 for 1 h at 37A degrees C), and was highly thermostable (retaining > 90% activity after incubation at 60A degrees C for 1 h at pH 7.0). These properties make XynA4 promising for application in the paper industry. This is the first report that describes cloning and expression of a xylanase gene from the genus Alicyclobacillus.

• 出版日期2010-2
• 单位中国农业科学院