Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Life Sciences Center, Vilnius University, Sauletekio 7, LT-10257, Vilnius, Lithuania.
Department of Research and Development Roquette Amilina, AB, J. Janonio 12, LT, 35101 Panevezys, Lithuania.
Chembiochem. 2024 Apr 16;25(8):e202400010. doi: 10.1002/cbic.202400010. Epub 2024 Mar 21.
A plethora of di- and oligosaccharides isolated from the natural sources are used in food and pharmaceutical industry. An enzymatic hydrolysis of fungal cell wall β-glucans is a good alternative to produce the desired oligosaccharides with different functionalities, such as the flavour enhancer gentiobiose. We have previously identified PsGly30A as a potential yeast cell wall degrading β-1,6-glycosidase. The aim of this study is to characterise the PsGly30A enzyme, a member of the GH30 family, and to evaluate its suitability for the production of gentiobiose from β-1,6-glucans. An endo-β-1,6-glucanase PsGly30A encoding gene from Paenibacillus sp. GKG has been cloned and overexpressed in Escherichia coli. The recombinant enzyme has been active towards pustulan and yeast β-glucan, but not on laminarin from the Laminaria digitata, confirming the endo-β-1,6-glucanase mode of action. The PsGly30A shows the highest activity at pH 5.5 and 50 °C. The specific activity of PsGly30A on pustulan (1262±82 U/mg) is among the highest reported for GH30 β-1,6-glycosidases. Moreover, gentiobiose is the major reaction product when pustulan, yeast β-glucan or yeast cell walls have been used as a substrate. Therefore, PsGly30A is a promising catalyst for valorisation of the yeast-related by-products.
从天然来源中分离得到的大量二糖和寡糖被用于食品和制药工业。真菌细胞壁β-葡聚糖的酶水解是生产具有不同功能的所需寡糖的一种很好的替代方法，例如作为风味增强剂的龙胆二糖。我们之前已经鉴定出 PsGly30A 是一种潜在的酵母细胞壁降解β-1,6-糖苷酶。本研究的目的是对属于 GH30 家族的 PsGly30A 酶进行表征，并评估其用于从β-1,6-葡聚糖生产龙胆二糖的适用性。已从 Paenibacillus sp. GKG 克隆并在大肠杆菌中过表达了编码内切-β-1,6-葡聚糖酶 PsGly30A 的基因。重组酶对普鲁兰聚糖和酵母β-葡聚糖具有活性，但对来自 Laminaria digitata 的昆布多糖没有活性，证实了内切-β-1,6-葡聚糖酶的作用模式。PsGly30A 在 pH 5.5 和 50°C 时表现出最高的活性。PsGly30A 对普鲁兰聚糖的比活性（1262±82 U/mg）在 GH30 β-1,6-糖苷酶中属于最高水平之一。此外，当使用普鲁兰聚糖、酵母β-葡聚糖或酵母细胞壁作为底物时，龙胆二糖是主要的反应产物。因此，PsGly30A 是一种很有前途的催化剂，可用于增值与酵母相关的副产物。
