Post-Graduate and Research Department of Zoology, Government College for Women, Thiruvananthapuram, Kerala, India.
World J Microbiol Biotechnol. 2022 Jul 1;38(9):148. doi: 10.1007/s11274-022-03340-2.
α-Galactosidase (α-D-galactosidase galactohydrolase; EC 3.2.1.22), is an industrially important enzyme that hydrolyzes the galactose residues in galactooligosaccharides and polysaccharides. The industrial production of α-galactosidase is currently insufficient owing to the high production cost, low production efficiency and low enzyme activity. Recent years have witnessed an increase in the worldwide research on molecular techniques to improve the production efficiency of microbial α-galactosidases. Cloning and overexpression of the gene sequences coding for α-galactosidases can not only increase the enzyme yield but can confer industrially beneficial characteristics to the enzyme protein. This review focuses on the molecular advances in the overexpression of α-galactosidases in bacterial and yeast/fungal expression systems. Recombinant α-galactosidases have improved biochemical and hydrolytic properties compared to their native counterparts. Metabolic engineering of microorganisms to produce high yields of α-galactosidase can also assist in the production of value-added products. Developing new variants of α-galactosidases through directed evolution can yield enzymes with increased catalytic activity and altered regioselectivity. The bottlenecks in the recombinant production of α-galactosidases are also discussed. The knowledge about the hurdles in the overexpression of recombinant proteins illuminates the emerging possibilities of developing a successful microbial cell factory and widens the opportunities for the production of industrially beneficial α-galactosidases.
α-半乳糖苷酶（α-D-半乳糖苷酶半乳糖水解酶；EC 3.2.1.22）是一种具有工业应用价值的酶，能够水解半乳糖寡糖和多糖中的半乳糖残基。由于生产成本高、生产效率低和酶活低，目前α-半乳糖苷酶的工业生产还远远不能满足需求。近年来，全球范围内对分子技术的研究不断增加，旨在提高微生物α-半乳糖苷酶的生产效率。克隆和过表达编码α-半乳糖苷酶的基因序列不仅可以提高酶的产量，还可以赋予酶蛋白工业上有利的特性。本文综述了在细菌和酵母/真菌表达系统中过表达α-半乳糖苷酶的分子进展。与天然同工酶相比，重组α-半乳糖苷酶具有更好的生化和水解特性。通过代谢工程对微生物进行改造以生产高产量的α-半乳糖苷酶，也有助于生产有附加值的产品。通过定向进化开发新型α-半乳糖苷酶，可以获得具有更高催化活性和改变的区域选择性的酶。本文还讨论了α-半乳糖苷酶重组生产的瓶颈问题。对重组蛋白过表达障碍的了解，阐明了开发成功的微生物细胞工厂的新可能性，并为生产具有工业应用价值的α-半乳糖苷酶提供了更多机会。
