Influence of the aromatic moiety in α- And β-arylalanines on their biotransformation with phenylalanine 2,3-aminomutase from: Pantoea agglomerans

Andrea Varga, Gergely Bánóczi, Botond Nagy, László Csaba Bencze, Monica Ioana Toşa, Ákos Gellért, Florin Dan Irimie, János Rétey, L. Poppe, Csaba Paizs

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

In this study enantiomer selective isomerization of various racemic α- and β-arylalanines catalysed by phenylalanine 2,3-aminomutase from Pantoea agglomerans (PaPAM) was investigated. Both α- and β-arylalanines were accepted as substrates when the aryl moiety was relatively small, like phenyl, 2-, 3-, 4-fluorophenyl or thiophen-2-yl. While 2-substituted α-phenylalanines bearing bulky electron withdrawing substituents did not react, the corresponding substituted β-aryl analogues were converted rapidly. Conversion of 3- and 4-substituted α-arylalanines happened smoothly, while conversion of the corresponding β-arylalanines was poor or non-existent. In the range of pH 7-9 there was no significant influence on the conversion of racemic α- or β-(thiophen-2-yl)alanines, whereas increasing the concentration of ammonia (ammonium carbonate from 50 to 1000 mM) inhibited the isomerization progressively and decreased the amount of the by-product (i.e. (E)-3-(thiophen-2-yl)acrylic acid was detected). In all cases, the high ee values of the products indicated excellent enantiomer selectivity and stereospecificity of the isomerization except for (S)-2-nitro-α-phenylalanine (ee 92%) from the β-isomer. Substituent effects were rationalized by computational modelling revealing that one of the main factors controlling biocatalytic activity was the energy difference between the covalent regioisomeric enzyme-substrate complexes.

Original languageEnglish
Pages (from-to)56412-56420
Number of pages9
JournalRSC Advances
Volume6
Issue number61
DOIs
Publication statusPublished - 2016

    Fingerprint

ASJC Scopus subject areas

  • Chemical Engineering(all)
  • Chemistry(all)

Cite this

Varga, A., Bánóczi, G., Nagy, B., Bencze, L. C., Toşa, M. I., Gellért, Á., Irimie, F. D., Rétey, J., Poppe, L., & Paizs, C. (2016). Influence of the aromatic moiety in α- And β-arylalanines on their biotransformation with phenylalanine 2,3-aminomutase from: Pantoea agglomerans. RSC Advances, 6(61), 56412-56420. https://doi.org/10.1039/c6ra02964g