Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida, 32306-4390, USA.
NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, 91109, USA.
Chemistry. 2019 Mar 27;25(18):4732-4739. doi: 10.1002/chem.201805950. Epub 2019 Feb 27.
Pyrophosphate might have functioned as an energy storage/currency molecule on early Earth, essential for the emergence of life. Here we synthesized mineral membranes involving iron(II), iron(III), and other divalent metal cations (calcium, manganese, cobalt, copper, zinc, and nickel) and tested their ability to catalyze the formation of pyrophosphate from phosphate and acetyl phosphate across steep pH gradients in microfluidic devices. We studied the chemical compositions of the precipitate membranes (which included vivianite, goethite, and green rust) using in situ and ex situ micro-Raman spectroscopy. The yields of pyrophosphate were determined by aqueous P NMR spectroscopy. We found that Fe and Ca were the best catalysts for pyrophosphate synthesis among investigated ions; Fe and mixed-valence iron membranes were also able to promote pyrophosphate formation. In addition, the pH gradients across the membranes affected the pyrophosphate yields and the smallest pH gradient resulted in the highest yield. These results suggest a possible route of substrate phosphorylation in prebiotic hydrothermal systems.
焦磷酸可能在早期地球上充当能量储存/货币分子，对生命的出现至关重要。在这里，我们合成了涉及铁(II)、铁(III)和其他二价金属阳离子（钙、锰、钴、铜、锌和镍）的矿物膜，并在微流控装置中测试了它们在跨越陡峭 pH 梯度的情况下从磷酸盐和乙酰磷酸盐催化生成焦磷酸的能力。我们使用原位和异位微拉曼光谱研究了沉淀膜（包括蓝铁矿、针铁矿和绿锈）的化学成分。通过水相 P NMR 光谱确定了焦磷酸盐的产率。我们发现，在研究的离子中，Fe 和 Ca 是合成焦磷酸盐的最佳催化剂；Fe 和混合价铁膜也能够促进焦磷酸盐的形成。此外，膜两侧的 pH 梯度会影响焦磷酸盐的产率，而最小的 pH 梯度会导致最高的产率。这些结果表明，在原始热液系统中可能存在底物磷酸化的途径。
