Lee Charles C, Smith Michael, Kibblewhite-Accinelli Rena E, Williams Tina G, Wagschal Kurt, Robertson George H, Wong Dominic W S
United States Department of Agriculture, Agricultural Research Service, Western Regional Research Center, 800 Buchanan St., Albany, CA 94710, USA.
Curr Microbiol. 2006 Feb;52(2):112-6. doi: 10.1007/s00284-005-4583-9. Epub 2006 Jan 31.
Xylan is the major component of hemicellulose, and xylan should be fully utilized to improve the efficiencies of a biobased economy. There are a variety of industrial reaction conditions in which an active xylanase enzyme would be desired. As a result, xylanase enzymes with different activity profiles are of great interest. We isolated a xylanase gene (xyn10) from a Flavobacterium sp. whose sequence suggests that it is a glycosyl hydrolase family 10 member. The enzyme has a temperature optimum of 30 degrees C, is active at cold temperatures, and is thermolabile. The enzyme has an apparent Km of 1.8 mg/ml and kcat of 100 sec-1 for beechwood xylan, attacks highly branched native xylan substrates, and does not have activity against glucans.
木聚糖是半纤维素的主要成分，应充分利用木聚糖以提高生物基经济的效率。在各种工业反应条件下，都需要活性木聚糖酶。因此，具有不同活性谱的木聚糖酶备受关注。我们从黄杆菌属中分离出一个木聚糖酶基因（xyn10），其序列表明它是糖基水解酶家族10的成员。该酶的最适温度为30℃，在低温下具有活性，且热不稳定。对于山毛榉木聚糖，该酶的表观Km为1.8mg/ml，kcat为100秒-1，能作用于高度分支的天然木聚糖底物，且对葡聚糖无活性。
