Many amino acids are essential during some point of life. They are functionally diverse, serving as building blocks in protein, peptide and amino acid syntheses and playing crucial roles in pathways such as energy metabolism. The use of stable isotope labeled amino acids within metabolic research allows the analytical tracking of the amino acid or of a correspondingly labeled down field metabolite. The pathway and metabolite under study depend on both the amino acid and the labeling pattern. This specificity allows the researcher to take advantage of differences in overlapping pathways, which is not possible with natural abundance amino acids. Due to the versatility, researchers have used stable isotope labeled amino acids to study and verify nutritional requirements,1 to measure muscle protein synthesis,2 and for the confirmation of metabolic pathways such as amino acid synthesis.3
The stable isotope labeled amino acid selection offered by Isotec Stable Isotopes includes all the standard amino acids in varying labeling patterns as well as several other metabolically interesting amino acids. For the majority of the amino acids offered, S&P (sterility and pyrogen) tested material is routinely available and for all others, S&P testing can be requested.
1. a) Chapman, K.P.; Courtney-Martin, G.; Moore, A.M.; Langer, J.C.; Tomlinson, C.; Ball, R.O.; Pencharz, P.B.; Am. J. Clin. Nutr. 2010, 91, 958. b) Courtney-Martin, G.; Moore, A.M.; Ball, R.O.; Pencharz, P.B.; Pediatric Res. 2010, 67, 320.
2. a) Symons, T.B.; Sheffield-Moore, M.; Wolfe, R.R.; Paddon-Jones, D.; J. Am. Diet. Assoc. 2009, 109, 1582. b) Doessing, S.; Heinemeier, K.M.; Holm, L.; Mackey, A.L.; Schjerling, P.; Rennie, M.; Smith, K.; Reitelseder, S.; Kappelgaard, A.-M.; Rasmussen, M.;H.; Flyvbjerg, A.; Kjar, M.; J. Physiol. 2010, 588, 341. 3. Tomlinson, C.; Rafii, M.; Sgro, M.; Ball, R. O.; Pencharz, P.; Pediatric Res. 2011, 69, 46.