Evans J N, Tolman C J, Kanodia S, Roberts M F
Biochemistry. 1985 Oct 8;24(21):5693-8. doi: 10.1021/bi00342a001.
The novel compound 2,3-cyclopyrophosphoglycerate (CPP) is the major small molecule carbon pool in Methanobacterium thermoautotrophicum. High-field 13C NMR 13CO2 pulse/unenriched CO2 chase experiments have shown that the labeled CPP rapidly loses its 13C to an insoluble pool, while the CPP steady-state concentration is maintained (as monitored by 31P NMR spectroscopy). The biosynthesis of CPP from CO2, acetyl coenzyme A, and pyruvate as precursors has been established by a 13C NMR study of ethanol extracts of Mb. thermoautotrophicum fed with 13CO2, [1-13C]- and [2-13C]acetate, and [1-13C]pyruvate. That CPP is a post-phosphoenolpyruvate metabolite has been confirmed by in vitro experiments with cell extracts. A role for CPP in carbohydrate metabolism was established when [1-13C]glucose fed to cells resulted in the formation of [3-13C]CPP exclusively. Possible functions of CPP within the cell are discussed.
新型化合物2,3-环焦磷酸甘油酸（CPP）是嗜热自养甲烷杆菌中主要的小分子碳库。高场13C NMR 13CO2脉冲/未富集CO2追踪实验表明，标记的CPP迅速将其13C释放到一个不溶性池中，而CPP的稳态浓度得以维持（通过31P NMR光谱监测）。通过对用13CO2、[1-13C]-和[2-13C]乙酸盐以及[1-13C]丙酮酸喂养的嗜热自养甲烷杆菌乙醇提取物进行13C NMR研究，已确定了以CO2、乙酰辅酶A和丙酮酸为前体生物合成CPP的过程。通过细胞提取物的体外实验证实了CPP是磷酸烯醇丙酮酸后的代谢产物。当向细胞中加入[1-13C]葡萄糖仅导致[3-13C]CPP形成时，确定了CPP在碳水化合物代谢中的作用。文中讨论了CPP在细胞内可能的功能。
