Department of Chemistry, Faculty of Science, Ramkhamhaeng University, Bangkok, 10240, Thailand.
Office of National Higher Education Science Research and Innovation Policy Council, Ministry of Higher Education Science Research and Innovation, Bangkok, 10330, Thailand.
World J Microbiol Biotechnol. 2022 Jan 7;38(2):36. doi: 10.1007/s11274-021-03220-1.
4α-Glucanotransferase (4α-GTase) is unique in its ability to form cyclic oligosaccharides, some of which are of industrial importance. Generally, low amount of enzymes is produced by or isolated from their natural sources: animals, plants, and microorganisms. Heterologous expressions of these enzymes, in an attempt to increase their production for applicable uses, have been widely studied since 1980s; however, the expressions are mostly performed in the prokaryotic bacteria, mostly Escherichia coli. Site-directed mutagenesis has added more value to these expressed enzymes to display the desired properties beneficial for their applications. The search for further suitable properties for food application leads to an extended research in expression by another group of host organism, the generally-recognized as safe host including the Bacillus and the eukaryotic yeast systems. Herein, our review focuses on two types of 4α-GTase: the cyclodextrin glycosyltransferase and amylomaltase. The updated studies on the general structure and properties of the two enzymes with emphasis on heterologous expression, mutagenesis for property improvement, and their industrial applications are provided.
4α-葡聚糖转糖苷酶（4α-GTase）具有形成环状低聚糖的独特能力，其中一些具有工业重要性。通常，这些酶的产量很低，或者是从其天然来源：动物、植物和微生物中分离出来的。自 20 世纪 80 年代以来，人们一直在广泛研究这些酶的异源表达，以期增加其产量，以满足应用需求；然而，这些表达大多在原核细菌中进行，主要是大肠杆菌。定点突变使这些表达的酶更具价值，从而表现出有利于其应用的所需特性。为了寻找更适合食品应用的特性，人们进一步研究了另一组公认安全的宿主生物，包括芽孢杆菌和真核酵母系统的表达。本文综述了两种类型的 4α-GTase：环糊精糖基转移酶和淀粉麦芽糖酶。重点介绍了这两种酶的一般结构和特性的最新研究进展，包括异源表达、突变改善特性以及它们的工业应用。
