Thermostable xylanase from Streptomyces thermocyaneoviolaceus for optimal production of xylooligosaccharides |
| |
Authors: | Jae-Ho Shin Jun-Ho Choi Oh-Seuk Lee Young-Mok Kim Dong-Suk Lee Yun-Young Kwak Won-Chan Kim In-Koo Rhee |
| |
Affiliation: | (1) Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing, 100081, People’s Republic of China;(2) Institute of Biochemistry and Molecular Biology, College of Life Sciences, Lanzhou University, Lanzhou, 730000, People’s Republic of China; |
| |
Abstract: | A thermo stable xylanase was purified from Streptomyces thermocyaneoviolaceus M049 for the production of xylooligosaccharides from xylan. The enzyme showed thermostability by maintaining 65% of remaining enzyme activity after 1 h heat treatment at 70°C. The molecular weight of the purified protein was 35 kDa in SDS-PAGE, and the optimal pH and temperature for the enzymatic activity were pH 5.0 and 60°C, respectively. N-terminal amino acid sequences of the purified xylanase, DTITSNQTGTHNGYF, were similar to StxII from S. Thermoviolaceus and XlnB from S. lividans. Using those two genes, stxll and xlnB as probe DNA, a gene encoding xylanase, xynB, was cloned from genomic library of S. thermocyaneoviolaceus M049. The open reading frame of the xynB was composed of 1008 nucleotide sequences. Compared to N-terminal sequences from purified enzyme, it was proposed that the XynB contained a 40 amino acid long signal peptide to the N-terminus. For easy production and purification, a XynB overproduction strain was constructed using pET21a(+) and strain E. coli BLR(DE3). Consequently, the recombinant enzyme was tested for the production of xylooligosaccharides through TLC and HPLC analyses. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|