Increasing awareness of the presence of D-amino acid residues in proteins in the dominant ‘L-chiral biosphere’, and of the preferential use of one enantiomer of a metabolite versus the other is largely due to recent developments in rapidly-applicable, analytical-chemical methods; and the stretched hydrogel NMR method is one of these [1-5].
Fully differentiated mammalian erythrocytes have no sub-cellular organelles and yet they display compartmentation of lactate depending on whether it is generated by glycolysis or the glyoxalase pathway. Thus operational compartmentation exists based not on the chemistry of the groups in lactate but its stereoisomerism; we call this ‘chiral compartmentation’.
We confirmed that the glyoxalase pathway yields D-lactate with 1H and 2H NMR spectroscopy and stretched gelatin gels providing weight for the new concept, and pointing the way methodologically to its discovery in other cases of parallel metabolic pathways.
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