绿色木霉对淀粉的降解。I. 淀粉降解机制

Starch degradation by the mould Trichoderma viride. I. The mechanism of starch degradation.

作者信息

Schellart J A, Visser F M, Zandstra T, Middelhoven W J

出版信息

Antonie Van Leeuwenhoek. 1976;42(3):229-38. doi: 10.1007/BF00394119.

Abstract

The mechanism of starch degradation by the fungus Trichoderma viride was studied in strain CBS 354.44, which utilizes glucose, starch and dextrins but is unable to assimilate maltose. It was shown that the amylolytic enzyme system is completely extracellular, equally well induced by starch, amylose or amylopectin and that it consists mainly of enzymes of the glucoamylase type which yield glucose as the main product of starch hydrolysis. Small amounts of alpha-amylase are produced also. The enzymes produced in starch cultures degrade starch, amylose and amylopectin equally well. Enzyme synthesis in starch media takes place to a considerable extent after exhaustion of the carbon source when maximum growth has been attained. Low-molecular dextrins are degraded by extracellular enzymes of the glucoamylase type. These enzymes are produced in media containing starch or dextrins. Maltotriose is consumed for only one third leaving maltose in the culture filtrate. Maltose is hardly attacked and hardly induces any amylolytic enzyme activity. No stable alpha-glucosidase appears to be produced.

摘要

在菌株CBS 354.44中研究了绿色木霉降解淀粉的机制，该菌株利用葡萄糖、淀粉和糊精，但不能同化麦芽糖。结果表明，淀粉分解酶系统完全位于细胞外，淀粉、直链淀粉或支链淀粉对其诱导效果相同，且该系统主要由糖化酶类型的酶组成，淀粉水解的主要产物是葡萄糖。同时也产生少量的α-淀粉酶。在淀粉培养基中产生的酶对淀粉、直链淀粉和支链淀粉的降解效果相同。当达到最大生长量后，在碳源耗尽时，淀粉培养基中的酶合成仍会在相当程度上进行。低分子糊精可被糖化酶类型的细胞外酶降解。这些酶在含有淀粉或糊精的培养基中产生。麦芽三糖仅有三分之一被消耗，培养滤液中留下麦芽糖。麦芽糖几乎不被分解，也几乎不诱导任何淀粉分解酶活性。似乎不会产生稳定的α-葡萄糖苷酶。