Cao Wei, Watanabe Risa, Ishii Yoshitaka, Kirimura Kohtaro
Department of Applied Chemistry, Faculty of Science and Engineering, Waseda University, 3-4-1 Ohkubo, Shinjuku-ku, Tokyo 169-8555, Japan.
Waseda Research Institute for Science and Engineering, Waseda University, 3-4-1 Ohkubo, Shinjuku-ku, Tokyo 169-8555, Japan.
J Biosci Bioeng. 2023 Nov;136(5):347-352. doi: 10.1016/j.jbiosc.2023.08.007. Epub 2023 Sep 23.
Several alkyl glucosides exhibit various bioactivities. 1-Octyl β-d-glucopyranoside produced by organic synthesis is used as a nonionic surfactant. However, no convenient method has been developed for the selective production of alkyl α-glucosides (α-AGs), such as 1-octyl α-d-glucopyranoside (α-OG). Therefore, we developed a simple method for selective production of α-AGs using the glucosyl transfer enzyme XgtA, (E.C. 3.2.1.20), derived from Xanthomonas campestris WU-9701. When 0.80 M alkyl alcohol and 2.5 units XgtA were incubated in 2.0 mL of 30 mM HEPES-NaOH buffer (pH 8.0) containing 1.2 M maltose at 45 °C, a specific α-AG corresponding to each alkyl alcohol (C2-C10) was detected. Under the standard conditions, we examined the selective production of α-OG from 1-octanol and maltose using XgtA. The reaction product was isolated and identified as α-OG via H nuclear magnetic resonance and nuclear overhauser effect spectroscopy analyses. No other glucosylated products, such as maltotriose, were detected in the reaction mixture. Under the standard conditions at 45 °C for 96 h, 243 mM α-OG (71 g/L) was produced in one batch production. Moreover, the addition of glucose isomerase to the reaction mixture decreased the concentration of glucose released via the reaction and increased the amount of α-OG produced; 359 mM α-OG (105 g/L) was maximally produced at 96 h. In conclusion, this study demonstrates the selective production of α-AGs using a simple enzymatic reaction, and XgtA has the potential to selectively produce various α-AGs.
几种烷基葡糖苷具有多种生物活性。通过有机合成制备的1-辛基-β-D-吡喃葡萄糖苷用作非离子表面活性剂。然而,尚未开发出用于选择性生产烷基α-葡糖苷(α-AGs)的便捷方法,例如1-辛基-α-D-吡喃葡萄糖苷(α-OG)。因此,我们开发了一种使用源自野油菜黄单胞菌WU-9701的糖基转移酶XgtA(E.C. 3.2.1.20)选择性生产α-AGs的简单方法。当0.80 M烷基醇和2.5单位XgtA在45℃下于2.0 mL含1.2 M麦芽糖的30 mM HEPES-NaOH缓冲液(pH 8.0)中孵育时,检测到对应于每种烷基醇(C2-C10)的特定α-AG。在标准条件下,我们使用XgtA研究了由1-辛醇和麦芽糖选择性生产α-OG的过程。通过氢核磁共振和核Overhauser效应光谱分析分离并鉴定反应产物为α-OG。在反应混合物中未检测到其他糖基化产物,如麦芽三糖。在45℃的标准条件下反应96小时,一批生产中产生了243 mM α-OG(71 g/L)。此外,向反应混合物中添加葡萄糖异构酶可降低反应释放的葡萄糖浓度并增加α-OG的产量;在96小时时最大产量为359 mM α-OG(105 g/L)。总之,本研究证明了通过简单的酶促反应选择性生产α-AGs,并且XgtA具有选择性生产各种α-AGs的潜力。