Pyrophosphate synthesis in iron mineral films and membranes simulating prebiotic submarine hydrothermal precipitates

作者：Barge Laura M^*; Doloboff Ivria J; Russell Michael J; VanderVelde David; White Lauren M; Stucky Galen D; Baum Marc M; Zeytounian John; Kidd Richard; Kanik Isik

来源：Geochimica et Cosmochimica Acta, 2014, 128: 1-12.

DOI：10.1016/j.gca.2013.12.006

Cells use three main ways of generating energy currency to drive metabolism: (i) conversion of adenosine diphosphate (ADP) to adenosine triphosphate (ATP) by the proton motive force through the rotor-stator ATP synthase; (ii) the synthesis of inorganic phosphate similar to phosphate bonds via proton (or sodium) pyrophosphate synthase; or (iii) substrate-level phosphorylation through the direct donation from an active phosphoryl donor. A mechanism to produce a pyrophosphate bond as "energy currency" in prebiotic systems is one of the most important considerations for origin of life research. Baltscheffsky (1996) suggests that inorganic pyrophosphate (P2O74-; PPi) may have preceded ATP/ADP as an energy storage molecule in earliest life, produced by an H+ pyrophosphatase. Here we test the hypothesis that PPi could be synthesized in inorganic precipitates simulating hydrothermal chimney structures transected by thermal and/or ionic gradients. Appreciable yields of PPi were obtained via substrate phosphorylation by acetyl phosphate within the iron sulfide/silicate precipitates at temperatures expected for an alkaline hydrothermal system.

• 出版日期2014-3-1