Seely R J, Fahrney D E
J Biol Chem. 1983 Sep 25;258(18):10835-8.
A phosphorus-containing metabolite that accounts for up to 80% of the total phosphate in perchloric acid extracts of Methanobacterium thermoautotrophicum ATCC 29183 was purified by chromatography on an anion exchange column. The proton-decoupled 31P NMR spectrum of the sodium salt in D2O exhibits an AB quartet with lines at -9.48, -9.78, -10.78, and -11.08 ppm upfield from 85% phosphoric acid. The phosphorus-phosphorus coupling constant is 18.5 Hz, a value characteristic of a pyrophosphate linkage. The structure of this compound has been tentatively established as cyclic-2,3-diphosphoglycerate (Kanodia, S., and Roberts, M. F. (1983) Proc. Natl. Acad. Sci. U.S.A., in press). Although rapidly degraded in neutral cell extracts, the diphosphodiester was stable for hours in cells whose metabolism had been arrested by depletion of H2 from the medium. If the cells were transferred to phosphate-free medium in the presence of H2 and CO2, the diester disappeared in about one cell generation. These findings point to a possible role as a phosphate storage compound, but the real function(s) of this unusual diphosphodiester must await a complete analysis of its structure and further metabolic studies.
一种含磷代谢物在嗜热自养甲烷杆菌ATCC 29183的高氯酸提取物中占总磷酸盐的80%，通过阴离子交换柱色谱法进行了纯化。该钠盐在D2O中的质子去耦31P NMR谱显示一个AB四重峰，其谱线相对于85%磷酸在-9.48、-9.78、-10.78和-11.08 ppm的高场处。磷-磷耦合常数为18.5 Hz，这是焦磷酸键的特征值。该化合物的结构已初步确定为环-2,3-二磷酸甘油酸（卡诺迪亚，S.，和罗伯茨，M. F.（1983年）《美国国家科学院院刊》，即将发表）。尽管在中性细胞提取物中会迅速降解，但该二磷酸二酯在因培养基中氢气耗尽而使代谢停止的细胞中能稳定存在数小时。如果在有氢气和二氧化碳存在的情况下将细胞转移到无磷酸盐培养基中，该二酯在大约一代细胞的时间内就会消失。这些发现表明它可能作为一种磷酸盐储存化合物，但这种不寻常的二磷酸二酯的真正功能必须等待对其结构进行全面分析以及进一步的代谢研究。
