摘要

Ammonia lyases catalyse the reversible addition of ammonia to cinnamic acid (1: R = H) and p-hydroxycinnamic (1: R = OH) to generate L-phenylalanine (2: R = H) and L-tyrosine (2: R = OH) respectively (Figure la). Both phenylalanine ammonia lyase (PAL) and tyrosine ammonia lyase (TAL) are widely distributed in plants, fungi and prokaryotes. Recently there has been interest in the use of these enzymes for the synthesis of a broader range of L-arylalanines. Aminomutases catalyse a related reaction, namely the interconversion of alpha-amino acids to beta-amino acids (Figure 1b). In the case of L-phenylalanine, this reaction is catalysed by phenylalanine aminomutase (PAM) and proceeds stereospecifically via the intermediate cinnamic acid to generate beta-Phe 3. Ammonia lyeses and aminomutases are related in sequence and structure and share the same active site cofactor 4-methylideneimidazole-5-one (Iwo). There is currently interest in the possibility of using these biocatalysts to prepare a wide range of enantiomerically pure L-configured alpha-amino and beta-amino acids. Recent reviews have focused on the mechanism of these MIO containing enzymes. The aim of this review is to review recent progress in the application of ammonia lyase and aminomutase enzymes to prepare enantiomerically pure alpha-amino and beta-amino acids.

  • 出版日期2011-4