In the plant kingdom beta-glucosidases (BGLUs) of the glycosidase hydrolase family 1 have essential function in primary metabolism and are particularly employed in secondary metabolism. They are essential for activation in two-component defence systems based on stabilisation of reactive compounds by glycosylation. Based on de novo assembly we isolated and functionally characterised BGLUs expressed in leaves of Lamium galeobdolon (LgGLUs). LgGLU1 could be assigned to hydrolysis of the benzoxazinoid GDIBOA (2,4-dihydroxy-1,4-benzoxazin-3-one glucoside). Within the Lamiaceae L. galeobdolon is distinguished by the presence GDIBOA in addition to the more common iridoid harpagide. Although LgGLU1 proved to be promiscuous with respect to accepted substrates, harpagide hydrolysis was not detected. Benzoxazinoids are characteristic defence compounds of the Poales but are also found in some unrelated dicots. The benzoxazinoid specific BGLUs have recently been identified for the grasses maize, wheat, rye and the Ranunculaceae Consolida orientalis. All enzymes share a general substrate ambiguity but differ in detailed substrate pattern. The isolation of the second dicot GDIBOA glucosidase LgGLU1 allowed it to analyse the phylogenetic relation of the distinct BGLUs also within dicots. The data revealed long periods of independent sequence evolution before speciation.

中文翻译：

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混杂的 β-葡萄糖苷酶参与 Lamium galeobdolon 中的苯并恶嗪类去糖基化

在植物界中，糖苷酶水解酶家族 1 的 β-葡糖苷酶 (BGLU) 在初级代谢中具有重要功能，特别适用于次级代谢。它们对于基于通过糖基化稳定反应性化合物的双组分防御系统的激活至关重要。基于从头组装，我们分离并在功能上表征了在 Lamium galeobdolon (LgGLUs) 的叶子中表达的 BGLU。LgGLU1 可用于 benzoxazinoid GDIBOA（2,4-dihydroxy-1,4-benzoxazin-3-one 葡萄糖苷）的水解。在唇形科 L. galeobdolon 中，除了更常见的虹彩石 harpagide 外，还有 GDIBOA 的存在。尽管 LgGLU1 被证明与可接受的底物是混杂的，但未检测到哈帕格特水解。苯并恶嗪类化合物是 Poales 特有的防御化合物，但也存在于一些不相关的双子叶植物中。最近已为禾本科玉米、小麦、黑麦和毛茛科 Consolida orientalis 鉴定了苯并恶嗪类特异性 BGLU。所有酶都有一个普遍的底物模糊性，但在详细的底物模式上有所不同。第二个双子叶植物 GDIBOA 葡萄糖苷酶 LgGLU1 的分离使其能够分析双子叶植物中不同 BGLU 的系统发育关系。数据揭示了物种形成之前的长期独立序列进化。第二个双子叶植物 GDIBOA 葡萄糖苷酶 LgGLU1 的分离使其能够分析双子叶植物中不同 BGLU 的系统发育关系。数据揭示了物种形成之前的长期独立序列进化。第二个双子叶植物 GDIBOA 葡萄糖苷酶 LgGLU1 的分离使其能够分析双子叶植物中不同 BGLU 的系统发育关系。数据揭示了物种形成之前的长期独立序列进化。