L-Proline-d3 is intended for use as an internal standard for the quantification of L-proline by GC- or LC-MS. L-Proline is a nonessential amino acid.1 It contains a pyrrolidine ring, which contains the α-amino nitrogen, and is highly rigid, properties that affect protein conformation and folding and can cause kinks and turns in protein secondary structure.1,2 It is a substrate for the proton-coupled amino acid transporter 1 (PAT1) and an inhibitor of acetylcholinesterase (AChE; Ki = 86 µM).3,4 L-Proline accumulates in plants under environmental stress and is important for environmental stress tolerance through its involvement in protein synthesis, redox balance maintenance, osmoprotection, and signaling.5
1.Lodish, H., Berk, A., Zipursky, L., et al.Hierarchical structure of proteinsMolecular cell biology(2000) 2.MacArthur, M.W., and Thornton, J.M.Influence of proline residues on protein conformationJ. Mol. Biol.218(2)397-412(1991) 3.Thondorf, I., Voigt, V., SchÄfer, S., et al.Three-dimensional quantitative structure-activity relationship analyses of substrates of the human proton-coupled amino acid transporter 1 (hPAT1)Bioorg. Med. Chem.19(21)6409-6418(2011) 4.VÉgner, L., Peragovics, Á., Tombor, L., et al.Experimental confirmation of new drug-target interactions predicted by drug profile matchingJ. Med. Chem.56(21)8377-8388(2013) 5.Szabados, L., and SavourÉ, A.Proline: A multifunctional amino acidTrends Plant Sci.15(2)89-97(2010)