Petroselinum crispum phenylalanine ammonialyase (1U)

• 英文名称: Petroselinum crispum phenylalanine ammonialyase (1U)

反应信息

• 作为试剂：
  描述：

  (E)-3-(3-氯苯基)-2-丙烯酸 在 Petroselinum crispum phenylalanine ammonialyase (1U) ammonium hydroxide 作用下， 反应 24.0h， 以99%的产率得到3-氯-L-苯丙氨酸
  参考文献：
  名称：

  Phenylalanine Ammonia-Lyase: The Use of Its Broad Substrate Specificity for Mechanistic Investigations and Biocatalysis—Synthesis ofL-Arylalanines

  摘要：

  Several fluoro- and chlorophenylalanines were found to be good substrates of phenylalanine ammonialyase (PAL/EC 4.3.1.5) from parsley. The enantiomerically pure L-amino acids were obtained in goad yields by reaction of the corresponding cinnamic acids with 5M ammonia solution (buffered to pH 10) in the presence of PAL. The kinetic constants for nine different fluoro- and chlorophenylalanines do not provide a rigorous proof for but are consistent with the previously proposed mechanism comprising an electrophilic attack of the methylidene-imidazolone cofactor of PAL at the aromatic nucleus as a first chemical step. In the resulting Friedel-Crafts-type sigma complex the beta-protons are activated for abstraction and consequently the pro-S is abstracted by an enzymic base. Results from semiempirical calculations combined with a proposed partial active site model showed a correlation between the experimental kinetic constants and the change in polarization of the pro-S Cd-H bond and heat of formation of the ir complexes, thus making the electrophilic attack at the neutral aromatic ring plausible. Furthermore, while 5-pyrimidinylalanine was found to be a moderately good substrate of PAL, 2-pyrimidinylalanine was an inhibitor.

  DOI：

  10.1002/1521-3765(20000915)6:18<3386::aid-chem3386>3.0.co;2-5