Hensgens C M, Santos H, Zhang C, Kruizinga W H, Hansen T A
Department of Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, The Netherlands.
Eur J Biochem. 1996 Dec 1;242(2):327-31. doi: 10.1111/j.1432-1033.1996.0327r.x.
Under certain growth conditions the sulfate-reducing bacterium Desulfovibrio gigas forms electron-dense granules in the cells which had been claimed to consist of a magnesium triphosphate). We observed granules after cultivation in media with a low Fe2+ or NH4+ concentration and reinvestigated the nature of the electron-dense bodies. Energy-dispersive X-ray analysis of the granules in the cells showed that they contain large amounts of P, Mg, and K. Gel electrophoresis and chromatographic analyses of isolated granules which had been dissolved in 20 mM EDTA, however, revealed discrepancies with commercially available polyphosphates. 31P-NMR spectra also lacked the peaks in the -22-ppm region which are characteristic for inner phosphates of polyphosphates confirming that the phosphocompound as isolated from the electron-dense bodies of D. gigas did not consist of polyphosphates. Using multinuclear NMR spectroscopy we showed that the electron-dense bodies of D. gigas contained a novel metabolite which was identified as alpha-glucose 1,2,3,4,6-pentakis(diphosphate).
在特定生长条件下，硫酸盐还原菌巨大脱硫弧菌会在细胞内形成电子致密颗粒，据称这些颗粒由三磷酸镁组成。我们在低Fe2+或NH4+浓度的培养基中培养后观察到了颗粒，并重新研究了这些电子致密体的性质。对细胞内颗粒的能量色散X射线分析表明，它们含有大量的P、Mg和K。然而，对溶解在20 mM EDTA中的分离颗粒进行凝胶电泳和色谱分析，发现与市售多聚磷酸盐存在差异。31P-NMR光谱在-22 ppm区域也没有多聚磷酸盐内部磷酸盐特有的峰，这证实了从巨大脱硫弧菌电子致密体中分离出的磷化合物不是由多聚磷酸盐组成。使用多核NMR光谱，我们表明巨大脱硫弧菌的电子致密体含有一种新的代谢物，鉴定为α-葡萄糖1,2,3,4,6-五（二磷酸）。
