Resolution Of DL-Amino Acids Using Aminopeptidase B

Chiral is one of the basic properties of nature. Most molecules of constituting living organism are asymmetric chiral molecules, which play important physiological functions in vivo. Amino acid is a kind of chiral compound, and is widely used in several industries related to human life and health such as medicine, food, health products, feed and so on. D-amino acids, the synthetic intermediates, are widely used in the preparation of antibiotics, peptide hormone, pesticides and artificial sweeteners.Generally, amino acids can be prepared by fermentation, chemosynthesis or enzymatic synthesis. Compared with chemical synthesis, enzymatic synthesis has many advantages such as high efficiency, environment-friendly and safety. With increased environmental awareness, people have increasingly paid attention to comprehensive utilization of resources, clean production, low-carbon and energy conservation, which have become a global trend of development. Sustainable development, namely with minimal environmental impact, minimal resource consumption and the optimal management model to achieve the most reasonable economic growth, has become consensus on economic and social development fields.Different D,L-aminoamides were resoluted via Aminopeptidase B, and the conversion conditions were optimized, the specific work is as follows:D,L-phenylalaninamide was Chemical synthetized in D,L-phenylalanine as raw materials. Aminopeptidase B was enzymatic resoluted, respectively got D-phenylalaninamide and L-phenylalaninamide. Several factors of this enzymatic reaction were investigated. The optimal temperature and pH are37℃and9.0.The optimal concentration of phenylalanine is0.06mol/l.Mg2+with a concentration of1×10-3mol/l obviously active the reaction, while Zn2+and Cu2+show clearly inhibitory effect.This paper has also studied Aminopeptidase B enzymatic resolute Tryptophanamidewse, Leucylmide, Isoleucinamide, Methioninamide, Glutamine, Valinamide and Asparagine. Several factors were investigated like temperature and concentration. From the experimental results, the sequence of the combine ability with Aminopeptidase B of acid amides is aliphatic acid amide, aromatic acid amide and heterocycle-acid amide.Using molecular docking software, this paper studied the coalescent of Aminopeptidase B and different amide ligands in molecular level and verified the previous experimental results in the theory. Because the smaller space structure, aliphatic acid amide were vulnerable to combine with Aminopeptidase B, while aromatic acid amide was harder to combine for the benzene ring. With the largest space structure, no molecular docking results can be resulted of heterocycle-acid amide.