Substituting citrate for homocitrate in the M‐cluster of Mo‐nitrogenase shifts CO reduction from H₂ evolution toward hydrocarbon formation and conversely N₂ reduction from NH₃ formation toward H₂ evolution. This suggests a crucial role for homocitrate in substrate reduction by nitrogenase and the possibility to modulate product profiles of nitrogenase reactions by substituting the organic ligand of the cofactor.

中文翻译：

---

含有柠檬酸盐取代辅因子的 Mo 固氮酶变体的表征。

用柠檬酸盐替代 Mo-固氮酶M 簇中的高柠檬酸盐，将 CO 还原从 H ₂演化转变为碳氢化合物形成，相反，N ₂还原从 NH ₃形成转变为 H ₂演化。这表明高柠檬酸在固氮酶的底物还原中起关键作用，并且有可能通过取代辅因子的有机配体来调节固氮酶反应的产物谱。