Enzymatic synthesis of salicin glycosides through transglycosylation catalyzed by amylosucrases from Deinococcus geothermalis and Neisseria polysaccharea

Graduate School of Biotechnology, and Institute of Life Science and Resources, Kyung Hee University, Yongin 446-701, Republic of Korea.
Carbohydrate research (Impact Factor: 1.93). 04/2009; 344(13):1612-9. DOI: 10.1016/j.carres.2009.04.019
Source: PubMed


Amylosucrase (ASase, EC is a member of family 13 of the glycoside hydrolases that catalyze the synthesis of an alpha-(1-->4)-linked glucan polymer from sucrose instead of an expensive activated sugar, such as ADP- or UDP-glucose. Transglycosylation reactions mediated by the ASases of Deinococcus geothermalis (DGAS) and Neisseria polysaccharea (NPAS) were applied to the synthesis of salicin glycosides with sucrose serving as the glucopyranosyl donor and salicin as the acceptor molecule. Two salicin glycoside transfer products were detected by TLC and HPLC analyses. The synthesis of salicin glycosides was very efficient with NPAS with a yield of over 90%. In contrast, DGAS specifically synthesized only one salicin transglycosylation product. The transglycosylation products were identified as alpha-d-glucopyranosyl-(1-->4)-salicin (glucosyl salicin) and alpha-D-glucopyranosyl-(1-->4)-alpha-D-glucopyranosyl-(1-->4)-salicin (maltosyl salicin) by NMR analysis. The ratio between donor and acceptor had a significant effect on the type of product that resulted from the transglycosylation reaction. With more acceptors present in the reaction, more glucosyl salicin and less maltosyl salicin were synthesized.

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Available from: Moo-Yeol Baik, Oct 03, 2014
    • "The Ams-like sequences were revealed in 53 bacterial species: 21 Proteobacteria, 18 Cyanobacteria, and all Firmicutes lacked the ams genes. The function of Ams has been proved mainly in the sucrose-utilizing heterotrophic bacteria Neisseria polysaccharea, Deinococcus radiodurans , and Deinococcus geothermalis (Jung et al. 2009; van der Veen et al. 2006; Pizzut-Serin et al. 2005; Emond et al. 2008; Ha et al. 2009), and in the sucrose-synthesizing cyanobacterium Synechococcus sp. 7002 (Perez-Cenci and Salerno 2014). "
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    • "Gene cloning, expression, enzyme extraction, and purification were carried out as previously described [16]. Nickel-nitrilotriacetic acid (Ni-NTA) affinity column chromatography (Qiagen, Hilden, Germany) was used to purify recombinant His 6 -tagged NpAS. "
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