Li Yanhong, Xue Mengyang, Sheng Xue, Yu Hai, Zeng Jie, Thon Vireak, Chen Yi, Muthana Musleh M, Wang Peng G, Chen Xi
Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA.
Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA; National Glycoengineering Research Center and Shandong Province Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Jinan, Shandong 250100, China.
Bioorg Med Chem. 2016 Apr 15;24(8):1696-705. doi: 10.1016/j.bmc.2016.02.043. Epub 2016 Mar 3.
β1-3-N-Acetylglucosaminyltransferases (β3GlcNAcTs) and β1-4-galactosyltransferases (β4GalTs) have been broadly used in enzymatic synthesis of N-acetyllactosamine (LacNAc)-containing oligosaccharides and glycoconjugates including poly-LacNAc, and lacto-N-neotetraose (LNnT) found in the milk of human and other mammals. In order to explore oligosaccharides and derivatives that can be synthesized by the combination of β3GlcNAcTs and β4GalTs, donor substrate specificity studies of two bacterial β3GlcNAcTs from Helicobacter pylori (Hpβ3GlcNAcT) and Neisseria meningitidis (NmLgtA), respectively, using a library of 39 sugar nucleotides were carried out. The two β3GlcNAcTs have complementary donor substrate promiscuity and 13 different trisaccharides were produced. They were used to investigate the acceptor substrate specificities of three β4GalTs from Neisseria meningitidis (NmLgtB), Helicobacter pylori (Hpβ4GalT), and bovine (Bβ4GalT), respectively. Ten of the 13 trisaccharides were shown to be tolerable acceptors for at least one of these β4GalTs. The application of NmLgtA in one-pot multienzyme (OPME) synthesis of two trisaccharides including GalNAcβ1-3Galβ1-4GlcβProN3 and Galβ1-3Galβ1-4Glc was demonstrated. The study provides important information for using these glycosyltransferases as powerful catalysts in enzymatic and chemoenzymatic syntheses of oligosaccharides and derivatives which can be useful probes and reagents.
β1-3-N-乙酰葡糖胺基转移酶（β3GlcNAcTs）和β1-4-半乳糖基转移酶（β4GalTs）已广泛用于酶促合成含N-乙酰乳糖胺（LacNAc）的寡糖和糖缀合物，包括在人类和其他哺乳动物乳汁中发现的多聚-LacNAc和乳糖-N-新四糖（LNnT）。为了探索可通过β3GlcNAcTs和β4GalTs组合合成的寡糖及其衍生物，分别使用包含39种糖核苷酸的文库，对来自幽门螺杆菌（Hpβ3GlcNAcT）和脑膜炎奈瑟菌（NmLgtA）的两种细菌β3GlcNAcTs进行了供体底物特异性研究。这两种β3GlcNAcTs具有互补的供体底物混杂性，并产生了13种不同的三糖。它们分别用于研究来自脑膜炎奈瑟菌（NmLgtB）、幽门螺杆菌（Hpβ4GalT）和牛（Bβ4GalT）的三种β4GalTs的受体底物特异性。结果表明，13种三糖中的10种至少是其中一种β4GalTs可耐受的受体。证明了NmLgtA在一锅多酶（OPME）合成两种三糖（包括GalNAcβ1-3Galβ1-4GlcβProN3和Galβ1-3Galβ1-4Glc）中的应用。该研究为将这些糖基转移酶用作寡糖及其衍生物的酶促和化学酶促合成中的强大催化剂提供了重要信息，这些寡糖及其衍生物可能是有用的探针和试剂。
