木聚糖酶菌株的筛选及酶切位点的分析

Xylanase strain screening and restriction sites analysis

关键词:  菌株筛选  木聚糖酶  酶解  位点

Key words:  strain screening  xylanase  zymohydrolysis site

摘要:

以甘蔗残渣木聚糖为原料，通过唯一碳源选择性培养基筛选水解木聚糖的菌株，并对该菌株酶解木聚糖的条件进行了优化和酶切位点的推测。结果表明，温度60 ℃、时间30 min、pH6.0时为最佳酶促反应条件，在该条件下菌株不能完全降解木聚糖，说明该菌株含有对木聚糖酶解的单酶，其酶活达到6.494 U/mL；根据对直链淀粉的酶切分析，酶切位点是以16～18个葡萄糖为最小单位进行的，这种低聚糖的产生可能为今后的木聚糖或淀粉的应用开拓新领域。

Abstract:

Taking the xylan of sugar cane residue as raw material，the authors screened hydrolysis of xylan bacterial strain through the only carbonous and selective medium，then optimized the conditions and estimated restriction enzyme cutting site on what had been selected. The results suggested that the optimum reaction conditions were under 60 ℃，pH=6.0 and reaction time 30 min but xylan couldn’t be degraded completely by strains under this condition，it approved that the strains contained single enzyme of xylanase. Xylanase activity could reach 6.494 U/mL；on the basis of restriction analysis of amylase，the restriction sites opened at the 16-18 glucoses as the smallest unit. The discovered oligosaccharides might open a new field for application of xylan and starch in the future.