豆科植物和根瘤菌之间的特殊伙伴关系依赖于一种化学对话。植物类黄酮激活细菌转录因子NodD，该转录因子触发Nod因子的产生并被植物识别。通过对豌豆（Pisum sativum）共生体豆科根瘤菌（Rhizobium leguminosarum NodD）的结构研究，揭示了其被黄酮类化合物激活所必需的两个口袋。与紫花苜蓿（Medicago truncatula）的共生体Sinorhizobium medicae NodD1的比较研究表明，这种特异性是由口袋形状和特定氨基酸决定的。含有黄酮类化合物NodD1识别残基的嵌合NodD在豆科黄酮类化合物NodD主干中足以补充黄酮类化合物NodD1突变体在短尾黄酮类化合物中的固氮作用，证实了黄酮类化合物识别在寄主范围内的关键作用。
附：英文原文
Title: The molecular basis of the binding and specific activation of rhizobial NodD by flavonoids
Author: Yiting Ruan, Shangzhi Dong, Suyu Jiang, Yisheng Wang, Xiaotan Wu, Yuxin Zhuang, Wenjuan Wu, Alison K. East, Ping Xu, Philip S. Poole, Yu Zhang, Jeremy D. Murray
Issue&Volume: 2026-01-08
Abstract: The specific partnership between legumes and rhizobia relies on a chemical dialogue. Plant flavonoids activate the bacterial transcription factor NodD, which triggers production of Nod factors that are recognized by the plant. Structural studies of the Pisum sativum (pea) symbiont Rhizobium leguminosarum NodD revealed two pockets that are essential for its activation by flavonoids. Comparative studies with NodD1 of Sinorhizobium medicae, the symbiont of Medicago truncatula, revealed that this specificity is determined by the shape of the pocket and by specific amino acids. A chimeric NodD containing the flavonoid recognition residues from S. medicae NodD1 in the R. leguminosarum NodD backbone was sufficient to complement nitrogen fixation in M. truncatula by an S. medicae nodD1 mutant, confirming the critical role of flavonoid recognition in host range.
DOI: aec3061
Source: https://www.science.org/doi/10.1126/science.aec3061