两种镰刀菌葡萄糖淀粉酶部分酶学性质研究

Studies on Parts of Enzymatic Properties of Glucoamylase from Two Fusarium Strains

对串珠镰刀菌（Fusarium moniliforme）和禾谷镰刀菌（F.graminearum）所产葡萄糖淀粉酶部分酶学性质进行了研究,结果表明这2种镰刀菌产的葡萄糖淀粉酶的性质较为相似.50～60℃酶活性较高,最高酶活性出现在50℃,串珠镰刀菌比禾谷镰刀菌所产生的酶热稳定性稍高.pH 5.0～6.0之间酶活性较高,pH 5.0～8.0之间稳定.金属离子Mn2＋、Cu2＋对2种镰刀菌产酶的酶活性有较强的激活作用,其中Mn2＋激活作用最强烈,Mn2＋作用后禾谷镰刀菌和串珠镰刀菌葡萄糖淀粉酶的活性分别为对照的176％和173％.金属离子Na＋、Ca2＋及Fe2＋则会抑制这2种镰刀菌产葡萄糖淀粉酶的活性.

Parts of enzymatic properties of glucoamylase from two Fusarium strains,F.moniliforme and F.graminearum were studied.Enzymatic properties of the two Fusarium were similar.The optimal temperature of these two enzymes was 50 ℃ and the optimal pH range was 5.0～6.0.The enzymes were stable when the temperature was between 50～60 ℃ and pH ranged from 5.0 to 8.0.Glucoamylase from F.moniliforme had better thermal stability than that from F.graminearum.Glucoamylase activities were activated by Mn2＋ and Cu2＋,especially after Mn2＋ promoted its activities were 176％ and 173％ of control for F.moniliforme and F.graminearum,respectively.Glucoamylase activities of the two Fusarium were inhibited by Na＋,Ca2＋ and Fe2＋.