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NASA NTRS · 20040172675

Polymerization on the rocks: negatively-charged alpha-amino acids

Hill, A. R. Jr·Bohler, C.·Orgel, L. E.·Bada, J. L.
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Abstract

Oligomers of the negatively-charged amino acids, glutamic acid, aspartic acid, and O-phospho-L-serine are adsorbed by hydroxylapatite and illite with affinities that increase with oligomer length. In the case of oligo-glutamic acids adsorbed on hydroxylapatite, addition of an extra residue results in an approximately four-fold increase in the strength of adsorption. Oligomers much longer than the 7-mer are retained tenaciously by the mineral. Repeated incubation of short oligo-glutamic acids adsorbed on hydroxylapatite or illite with activated monomer leads to the accumulation of oligomers at least 45 units long. The corresponding reactions of aspartic acid and O-phospho-L-serine on hydroxylapatite are less effective in generating long oligomers, while illite fails to accumulate substantial amounts of long oligomers of aspartic acid or of O-phospho-L-serine.

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NASA Discipline ExobiologyNon-NASA CenterPeptides/chemical synthesis/chemistryBiogenesisAmino Acids, Dicarboxylic/chemistryMineralsAspartic Acid/chemistryAdsorptionGlutamic Acid/chemistrySupport, U.S. Gov't, Non-P.H.SDurapatiteElectrochemistryPhosphoserine/chemistryOligopeptides/chemical synthesis/chemistryModels, ChemicalChromatography, High Pressure Liquid

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Hill, A. R. Jr, Bohler, C., Orgel, L. E., Bada, J. L.. 1998-06-01. Polymerization on the rocks: negatively-charged alpha-amino acids. https://ntrs.nasa.gov/citations/20040172675

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