Department of Biochemistry and Applied Biosciences, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuen Kibanadai Nishi, Miyazaki 889-2192, Japan.
J Biosci Bioeng. 2010 Mar;109(3):227-9. doi: 10.1016/j.jbiosc.2009.09.005. Epub 2009 Oct 1.
An extracellular endo-1,4-beta-xylanase with specific activity of 566 U/mg was purified from the culture filtrate of a filamentous fungus, Aspergillus japonicus strain MU-2, grown on oat spelt xylan. The purified enzyme showed a single band on SDS-PAGE with an apparent M(r) of 25.1 kDa. Xylanase activity was optimal at pH 5.0 and 60 degrees C. The xylanase gene (xynA) encoded a 42 residue prepropeptide and a 191 residue mature protein. The XynA protein showed the highest sequence identity of 69% to Aspergillus niger XynB (DQ174549), which belongs to the glycoside hydrolase family 11.
从生长在燕麦黑麦木聚糖上的丝状真菌 Aspergillus japonicus 菌株 MU-2 的发酵滤液中纯化出一种具有 566 U/mg 比活的胞外内切-1,4-β-木聚糖酶。纯化的酶在 SDS-PAGE 上显示出单一带，表观 Mr 为 25.1 kDa。木聚糖酶活性在 pH 5.0 和 60°C 时最佳。木聚糖酶基因（xynA）编码一个 42 个氨基酸残基的前导肽和一个 191 个氨基酸残基的成熟蛋白。XynA 蛋白与属于糖苷水解酶家族 11 的 Aspergillus niger XynB（DQ174549）的同源性最高，为 69%。
