Analysis of 13C labeling amino acids by capillary electrophoresis - High resolution mass spectrometry in developing flaxseed.

In context of fluxomic studies, 13C labeling analysis of amino acids are very important for solving the carbon flow calculation, because they are synthesized in various biosynthesis pathways and cellular compartments in plant cells. Traditionally, 13C labeling analysis are performed using low resolution mass spectrometry detector by GC-MS. We compared a method using capillary electrophoresis-high resolution mass spectrometry without derivatization and with better accuracy assessment of labeling measurements comparing to classical GC-MS. Our method allowed us to show that valine, leucine, alanine are not synthesized from the same pyruvate pool during the period of reserves accumulation in flax seeds.