Journal of Molecular Evolution

, Volume 31, Issue 5, pp 353–358

Model for prebiotic pyrophosphate formation: Condensation of precipitated orthophosphate at low temperature in the absence of condensing or phosphorylating agents

  • Marcelo Hermes-Lima
Article

DOI: 10.1007/BF02106049

Cite this article as:
Hermes-Lima, M. J Mol Evol (1990) 31: 353. doi:10.1007/BF02106049

Summary

The formation of pyrophosphate (PPi) by condensation of orthophosphate (Pi) at low temperature (37°C) in the absence of condensing or phosphorylating agents could have been an ancient process in chemical evolution. In the present investigation the synthesis of32PPi from32Pi was carried out at pH 8.0 and PPi was found in larger amounts in the presence of insoluble Pi (with calcium or manganese ions) than in its absence (with magnesium ions, or with no divalent cations present). After 10 days of incubation in the presence of precipitated calcium phosphate, about 1.6 nmol/ml of PPi was formed (0.057% yield relative to insoluble Pi). The hypothesis that the reaction is dependent on precipitated Pi was reinforced by the effect of adding dimethyl sulfoxide (2.1–9.9 M) in the presence of magnesium ions: the amount of magnesium phosphate precipitated in the presence of the organic solvent was proportional to the amount of PPi formed. The large and negative activation entropies found in aqueous media with calcium ions and in a medium containing 11.3 M dimethyl sulfoxide with magnesium ions suggest that the reaction was favored by a hydrophobic phenomenon at the surface of solid Pi. This reaction could serve as a model for prebiotic formation of PPi.

Key words

Pyrophosphate formationPrecipitated calcium phosphateCondensation reactionChemical evolutionDimethyl sulfoxide

Copyright information

© Springer-Verlag New York Inc. 1990

Authors and Affiliations

  • Marcelo Hermes-Lima
    • 1
  1. 1.Departamento de Bioquímica, Instituto de Ciências BiomédicasUniversidade Federal do Rio de JaneiroRio de JaneiroBrazil
  2. 2.Departamento de Bioquímica, I.B.UNICAMPCampinasBrazil