论文标题
研究新的左您的范围与常规和非规定底物的产品曲线和结构关系
Investigating the Product Profiles and Structural Relationships of New Levansucrases with Conventional and Non-Conventional Substrates
论文作者
论文摘要
对于益生元的潜力及其在制药和食品工业中的作用，需要将复杂的寡糖的合成。葡萄糖酶（LS，EC 2.4.1.10），一种果糖基转移酶，可以催化这些化合物的合成。 LS通过$β$ - （2 $ \至$ 6） - 糖苷链接，从供体分子中获取果糖基残基，并对受体分子进行非列诺转移。基因组挖掘用于发现新的LS酶，具有增加的转染色性活性和更广泛的受体滥交，初始筛选揭示了五种LS酶。这些酶与蔗糖孵育后检查了这些酶的产品曲线和活性。还将替代的受体分子与酶一起孵育以研究其消耗。来自葡萄糖杆菌的LSS和芳香族芳烃合成的果糖（FOSS），长度高达13个单位。其氨基酸序列和底物与同源模型对接的比对确定了其产物光谱差异的结构元素。含蔗糖的含芬糖是来自颤音Natriegens，N。Aromaticivorans和Paraburkolderia graminis的LS的首选供体分子。发现所检查的LSS具有广泛的受体滥交，高度利用单糖，二糖和两种醇。
The synthesis of complex oligosaccharides is desired for their potential as prebiotics, and their role in the pharmaceutical and food industry. Levansucrase (LS, EC 2.4.1.10), a fructosyl-transferase, can catalyze the synthesis of these compounds. LS acquires a fructosyl residue from a donor molecule and performs a non-Lenoir transfer to an acceptor molecule, via $β$-(2$\to$6)-glycosidic linkages. Genome mining was used to uncover new LS enzymes with increased transfructosylating activity and wider acceptor promiscuity, with an initial screening revealing five LS enzymes. The product profiles and activities of these enzymes were examined after their incubation with sucrose. Alternate acceptor molecules were also incubated with the enzymes to study their consumption. LSs from Gluconobacter oxydans and Novosphingobium aromaticivorans synthesized fructooligosaccharides (FOSs) with up to 13 units in length. Alignment of their amino acid sequences and substrate docking with homology models identified structural elements causing differences in their product spectra. Raffinose, over sucrose, was the preferred donor molecule for the LS from Vibrio natriegens, N. aromaticivorans, and Paraburkolderia graminis. The LSs examined were found to have wide acceptor promiscuity, utilizing monosaccharides, disaccharides, and two alcohols to a high degree.
