Laboratoire de Microorganismes et de Biomolécules (LMB), Centre de Biotechnologie de Sfax (CBS), Université de Sfax, Route de Sidi Mansour Km 6, BP 1177 3018 Sfax, Tunisia.
Carbohydr Polym. 2013 Oct 15;98(1):967-75. doi: 10.1016/j.carbpol.2013.07.009. Epub 2013 Jul 11.
New β-1,3;1,4-glucanase was purified from Aspergillus niger US368. The pure glucanase has a molecular mass of about 32 kDa. The N-terminal sequence of the purified enzyme (A-G-T-N-P-P-I-G-V) was determined. The optimum pH and temperature recorded for enzyme activity were 5 and 60 °C, respectively. It also displayed marked thermostability with a half-life of 30 min at 70 °C. At 37 °C, the enzyme showed 100% stability from pH 3 to 10. The Km and Vmax values exhibited by the enzyme on barley β-glucan were 0.62 mg ml(-1) and 34.46 U ml(-1), respectively. The enzyme is a retaining-one and was only active toward glucan containing β-1,3;1,4-linkages. The production of β-glucanase with barley flour as the sole carbon source was optimized. This is the first report on the purification and characterization of a β-1,3;1,4-glucanase from A. niger. This lichenase could be considered as a candidate for future application particularly in the animal feed industry.
从黑曲霉 US368 中纯化出一种新的β-1,3;1,4-葡聚糖酶。该纯葡聚糖酶的分子量约为 32 kDa。纯化酶的 N 末端序列（A-G-T-N-P-P-I-G-V）已被确定。该酶活性的最适 pH 和温度分别为 5 和 60°C。它还表现出明显的热稳定性，在 70°C 下半衰期为 30 分钟。在 37°C 下，该酶在 pH 3 到 10 之间具有 100%的稳定性。该酶对大麦β-葡聚糖的 Km 和 Vmax 值分别为 0.62 mg ml(-1)和 34.46 U ml(-1)。该酶是一种保留型酶，仅对含有β-1,3;1,4-键的葡聚糖具有活性。以大麦粉为唯一碳源优化了β-葡聚糖酶的生产。这是首次从黑曲霉中纯化和表征β-1,3;1,4-葡聚糖酶的报道。这种木聚糖酶可以被认为是未来在动物饲料工业中应用的候选酶。
