l-Arabinose has been produced by hydrolyzing arabinan, a component of hemicellulose. However, l-arabinose has limitations in industrial applications owing to its relatively high cost. Here, d-xylulose 4-epimerase as a new-type enzyme was developed from d-tagaturonate 3-epimerase from Thermotoga petrophila using structure-guided enzyme engineering. d-Xylulose 4-epimerase, which epimerized d-xylulose to l-ribulose, d-xylulokinase and sugar phosphatase, which overcame the equilibrium of d-xylose isomerase, were included to establish a new efficient conversion pathway from d-xylose to l-arabinose. l-Arabinose at 34 g/L was produced from 100 g/L xylan in 45 h by multi-enzymatic cascade reaction using xylanase and enzymes involved in the established conversion pathway. As l-ribulokinase was used instead of d-xylulokinase in the established conversion pathway, an efficient reverse-directed conversion pathway from l-arabinose to d-xylose and the production of d-xylose from arabinan using arabinanase and enzymes involved in the proposed pathway are proposed.

中文翻译：

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通过多酶级联反应将木聚糖有效转化为 L-阿拉伯糖，其中包括 d-木酮糖 4-差向异构酶作为新型立体选择性交换酶


L-阿拉伯糖是通过水解阿拉伯聚糖（半纤维素的一种成分）产生的。然而，L-阿拉伯糖由于其相对较高的成本而在工业应用中受到限制。在这里，d-木酮糖4-差向异构酶作为一种新型酶，是利用结构引导酶工程从来自Thermotoga petropicila的d-塔谷糖酸3-差向异构酶开发而来。 d-木酮糖4-差向异构酶将d-木酮糖差向异构化为l-核酮糖，d-木酮糖激酶和糖磷酸酶克服了d-木糖异构酶的平衡，建立了一条新的从d-木糖到l-的高效转化途径。阿拉伯糖。使用木聚糖酶和参与已建立的转化途径的酶，通过多酶级联反应，在 45 小时内从 100 g/L 木聚糖生产出 34 g/L 的 L-阿拉伯糖。由于在已建立的转化途径中使用L-核酮糖激酶代替D-木酮糖激酶，因此从L-阿拉伯糖到D-木糖的有效反向转化途径以及使用阿拉伯聚糖酶和参与该途径的酶从阿拉伯聚糖生产D-木糖被提议。