Catalytic Prebiotic Formation of Glycerol Phosphate Esters and an Estimation of Their Steady State Abundance under Plausible Early Earth Conditions

Maheen Gull,Matthew A Pasek

doi:10.3390/catal11111384

Abstract

The emergence of biological phosphate esters of glycerol could have been a crucial step in the origin and evolution of life on the early Earth as glycerol phosphates today play a central role in biochemistry. We investigate here the formation of the glycerol phosphates by employing various rock samples, salts, and minerals as potential catalysts to aid the phosphorylation process. We report the synthesis of various phosphate esters of glycerol including glycerol-1-phosphate, glycerol-2-phosphate, cyclic glycerol-monophosphate as well as various diphosphate esters. Furthermore, the decomposition rates of glycerol phosphate under mild heating were also studied while keeping the pH constant. It was observed that glycerol phosphate starts decomposing quickly under mild heating conditions into inorganic orthophosphate and pyrophosphate, and a steady state concentration of ~0.5 M of glycerol phosphate may have been reasonable in ponds with abundant glycerol, phosphate, urea, and catalytic minerals.

Highlights

Glycerol phosphates (GP) play a central role in modern biochemistry
For a better understanding of the origin and evolution of early membranes, it is essential to understand the prebiotic syntheses of GP, which are critical to the synthesis of phospholipids, an essential component of cell membranes in almost all organisms [2,3,4]
We investigated GP decomposition under similar conditions in order to constrain a plausible steady-state concentration of GP on the early earth

Summary

Introduction

Glycerol phosphates (GP) play a central role in modern biochemistry. These compounds are directly associated with crucial life processes, such as cellular respiration and cell structure [1]. We have mimicked a prebiotically plausible drying hot pool of water containing a dissolved organic (glycerol), a condensation agent (urea), a phosphate (ammonium phosphate), along with various minerals including kaolinite, quartz, hematite, magnetite, olivine, ulexite, and salts (NH4 Cl, NaCl, Na2 CO3 ) and some relevant rock samples (serpentinite, obsidian, and basalt). These substances were investigated for their role in the formation of GP. We investigated GP decomposition under similar conditions in order to constrain a plausible steady-state concentration of GP on the early earth

Results and Discussions

Materials and Methods

Phosphorylation of Glycerol

Decomposition Reaction Studies of the Glycerol Phosphates