Key Laboratory of Chemical Biology of Natural Products, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, Jinan 250012, China.
Molecules. 2018 Jul 4;23(7):1630. doi: 10.3390/molecules23071630.
Alkenal double bond reductases (DBRs), capable of catalyzing the NADPH-dependent reduction of the α,β-unsaturated double bond, play key roles in the detoxication of alkenal carbonyls. Here, the isolation and characterization of two DBRs encoded by the liverwort species are described. The two DBRs share a relatively low similarity, and phylogenetic analysis indicated that MpMDBRL is more closely related to microbial DBRs than to other plant DBRs, while MpDBR shares common ancestry with typical plant DBRs. Both DBR proteins exhibited hydrogenation ability towards hydroxycinnamyl aldehydes; however, their temperature optimums were strikingly different. MpMDBRL demonstrated slightly weaker catalytic efficiency compared to MpDBR, and the structural models of their active binding sites to the substrate may provide a parsimonious explanation. Furthermore, both DBRs significantly responded to phytohormone treatment. In conclusion, produces two distinct types of functional DBRs, both of which participate in the protection against environmental stress in liverwort. The presence of a microbial type of DBR in a plant is herein reported for the first time.
烯醛双键还原酶（DBR）能够催化 NADPH 依赖型的α,β-不饱和双键还原，在烯醛羰基的解毒中发挥关键作用。本文描述了从地钱属植物中分离和鉴定的两种 DBR。这两种 DBR 具有相对较低的相似性，系统发育分析表明，MpMDBRL 与微生物 DBR 比其他植物 DBR 更为接近，而 MpDBR 与典型的植物 DBR 具有共同的进化起源。两种 DBR 蛋白均表现出对羟基肉桂醛的加氢能力；然而，它们的最适温度差异显著。与 MpDBR 相比，MpMDBRL 的催化效率略低，其与底物的活性结合位点的结构模型可能提供了一个简洁的解释。此外，两种 DBR 均对植物激素处理有明显的响应。总之，产生了两种不同类型的功能性 DBR，它们都参与了地钱对环境胁迫的保护。本文首次报道了在植物中存在微生物型 DBR。
