Huergo Luciano F, Dixon Ray
Instituto Nacional de Ciência e Tecnologia da Fixação Biológica de Nitrogênio, Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, Curitiba, PR, Brazil Setor Litoral, Universidade Federal do Paraná, Matinhos, PR, Brazil.
Department of Molecular Microbiology, John Innes Centre, Norwich, United Kingdom
Microbiol Mol Biol Rev. 2015 Dec;79(4):419-35. doi: 10.1128/MMBR.00038-15.
The metabolite 2-oxoglutarate (also known as α-ketoglutarate, 2-ketoglutaric acid, or oxoglutaric acid) lies at the intersection between the carbon and nitrogen metabolic pathways. This compound is a key intermediate of one of the most fundamental biochemical pathways in carbon metabolism, the tricarboxylic acid (TCA) cycle. In addition, 2-oxoglutarate also acts as the major carbon skeleton for nitrogen-assimilatory reactions. Experimental data support the conclusion that intracellular levels of 2-oxoglutarate fluctuate according to nitrogen and carbon availability. This review summarizes how nature has capitalized on the ability of 2-oxoglutarate to reflect cellular nutritional status through evolution of a variety of 2-oxoglutarate-sensing regulatory proteins. The number of metabolic pathways known to be regulated by 2-oxoglutarate levels has increased significantly in recent years. The signaling properties of 2-oxoglutarate are highlighted by the fact that this metabolite regulates the synthesis of the well-established master signaling molecule, cyclic AMP (cAMP), in Escherichia coli.
代谢物2-氧代戊二酸（也称为α-酮戊二酸、2-酮戊二酸或草酰戊二酸）处于碳代谢和氮代谢途径的交叉点。这种化合物是碳代谢中最基本的生化途径之一——三羧酸（TCA）循环的关键中间体。此外，2-氧代戊二酸还作为氮同化反应的主要碳骨架。实验数据支持这样的结论，即细胞内2-氧代戊二酸的水平会根据氮和碳的可利用性而波动。本综述总结了自然界如何通过进化出多种2-氧代戊二酸传感调节蛋白，利用2-氧代戊二酸反映细胞营养状态的能力。近年来，已知受2-氧代戊二酸水平调节的代谢途径数量显著增加。2-氧代戊二酸的信号特性体现在这种代谢物在大肠杆菌中调节成熟的主要信号分子环磷酸腺苷（cAMP）的合成这一事实上。
