Three different types of α-amylases from Aspergillus awamori KT-11:: Their purifications, properties, and specificities
Three different types of α-amylases from Aspergillus awamori KT-11:: Their purifications, properties, and specificities
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DOI：
10.1271/bbb.62.1351
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发表时间：
1998-07-01
影响因子：
1.6
通讯作者：
Minamiura, N
中科院分区：
文献类型：
--
作者：
Anindyawati, T;Melliawati, R;Minamiura, N
三种形式的α-淀粉酶，命名为Amyl I，Amyl II和Amyl III，通过几个柱层析从黑霉菌株的麦麸中的曲培养物中纯化至均质状态，该黑霉菌株分离于印度尼西亚并鉴定为泡盛曲霉（Aspergillus awamori）。SDS-PAGE测定其分子量分别为49，000、63，000和97，000，可溶性淀粉上Amyl I的最佳pH为4.0，Amyl II和Amyl III的最佳pH为5.5。Amyl I水解麦芽四糖、麦芽五糖、麦芽六糖、麦芽七糖以及β-和γ-环糊精，以产生麦芽糖和麦芽三糖作为主要产物，但不水解或几乎不水解麦芽糖、异麦芽糖、麦芽三糖、异麦芽三糖、α-环糊精或生玉米淀粉。另一方面，Amyl II和Amyl LII都水解麦芽三糖以及上述所有麦芽低聚糖和α-、β-和γ-环糊精，甚至原玉米淀粉以及热糊化玉米淀粉，以产生麦芽糖作为主要产物和葡萄糖和麦芽三糖作为次要产物，但它们不水解麦芽糖、异麦芽糖或异麦芽三糖。3种酶对可溶性淀粉的极限水解率分别为Amyl I 33%，Amyl II 35%，Amyl III 38%，NMR分析表明反应产物均为α-异头异构体，在淀粉水解18%左右，与I-2的蓝色反应完全消失。
Three forms of alpha-amylases, designated Amyl I, Amyl II, and Amyl III were purified to a homogenous state by several column chromatographies from a koji culture in wheat bran of a strain of black mold, which was isolated in Indonesia and identified as Aspergillus awamori. They have molecular weights of 49,000, 63,000, and 97,000 by SDS-PAGE, respectively, and the optimum pHs were 4.0 for Amyl I and 5.5 for both Amyl II and Amyl III on soluble starch. Amyl I hydrolyzed malto-tetraose, -pentaose, -hexaose, -heptaose, and beta- and gamma-cyclodextrin to produce maltose and maltotriose as major products but not or hardly hydrolyzed maltose, isomaltose, maltotriose, isomaltotriose, alpha-cyclodextrin, or raw corn starch. On the other hand, both Amyl II and Amyl LII hydrolyzed maltotriose as well as all the maltooligosaccharides described above and alpha-, beta-, and gamma-cyclodextrin, and even raw corn starch as well as heat-gelatinized corn starch to produce maltose as a major product and glucose and maltotriose as minor products, but they did not hydrolyze maltose, isomaltose, or isomaltotriose. The limit hydrolyses of soluble starch with three kinds of enzymes were 33% for Amyl I, 35% for Amyl II, and 38% for Amyl III, the reaction products had alpha-anomeric forms by NMR analysis, and the blue color reaction with I-2 disappeared completely at about 18% of hydrolysis of the starch for all enzymes.