Bara Maria Teresa F, Lima Adilson L, Ulhoa Cirano J
Faculdade de Farmácia, Universidade Federal de Goiás, 74.605-220, Goiânia, GO, Brazil.
FEMS Microbiol Lett. 2003 Feb 14;219(1):81-5. doi: 10.1016/S0378-1097(02)01191-6.
Trichoderma asperellum produces at least two extracellular beta-1,3-glucanases upon induction with cell walls from Rhizoctonia solani. A beta-1,3-glucanase was purified by gel filtration and ion exchange chromatography. A typical procedure provided 35.7-fold purification with 9.5% yield. The molecular mass of the purified exo-beta-1,3-glucanases was 83.1 kDa as estimated using a 12% (w/v) SDS-electrophoresis slab gel. The enzyme was only active toward glucans containing beta-1,3-linkages and hydrolyzed laminarin in an exo-like fashion to form glucose. The K(m) and V(max) values for exo-beta-1,3-glucanase, using laminarin as substrate, were 0.087 mg ml(-1) and 0.246 U min(-1), respectively. The pH optimum for the enzyme was pH 5.1 and maximum activity was obtained at 55 degrees C. Hg(2+) strongly inhibited the purified enzyme.
在用立枯丝核菌细胞壁诱导后，棘孢木霉至少会产生两种细胞外β-1,3-葡聚糖酶。通过凝胶过滤和离子交换色谱法纯化了一种β-1,3-葡聚糖酶。一个典型的程序实现了35.7倍的纯化，产率为9.5%。使用12%（w/v）SDS电泳平板凝胶估计，纯化的外切β-1,3-葡聚糖酶的分子量为83.1 kDa。该酶仅对含有β-1,3-连接的葡聚糖有活性，并以类似外切的方式水解海带多糖形成葡萄糖。以外切β-1,3-葡聚糖酶为例，以海带多糖为底物时，其K(m)和V(max)值分别为0.087 mg ml(-1)和0.246 U min(-1)。该酶的最适pH为5.1，在55℃时获得最大活性。Hg(2+)强烈抑制纯化后的酶。
Zotero 插件