Spectral analysis of 1 H coupled 13 C spectra of the amino acids: adaptive spectral library of amino acid 13 C isotopomers and positional fractional 13 C enrichments

The natural abundance 1 H‐coupled 13 C NMR spectra of all proteogenic amino acids were measured in D 2 O at pH* 1. The accurate 1 H, 13 C spin‐spin coupling constants were analyzed using total‐line‐shape fitting. The obtained spectral parameters can be used to establish a spectral library of amino acid 13 C isotopomers. The adaptive spectral library principle is introduced and discussed in this article. The simulated spectra can be applied to quantification of 13 C isotopomer mixtures of amino acids and, thus, for exploring metabolic pathways. Also a protocol for amino acid 13 C isotopomer metabolomic profiling in 13 C labeled glucose feeding experiments is outlined. The approach is suggested to give invaluable information about positional fractional 13 C enrichments, which are not easily available by any other method. Copyright © 2007 John Wiley & Sons, Ltd.