Characterization of benzaldehyde lyase from Pseudomonas fluorescens: A versatile enzyme for asymmetric C-C bond formation.
The thiamin-diphosphate-dependent enzyme benzaldehyde lyase is a very import catalyst for chemoenzymatic synthesis catalyzing the formation and cleavage of (R)-hydroxy ketones. We have studied the stability of the recombinant enzyme and some enzyme variants with respect to pH, temperature, buffer salt, cofactors and organic cosolvents. Stability of BAL in chemoenzymatic synthesis requires the addition of cofactors to the buffer. Reaction temperature should not exceed 37 degrees C. The enzyme is stable between pH 6 and 8, with pH 8 being the pH-optimum of both the lyase and the ligase reaction. Potassium phosphate and Tris were identified as optimal reaction buffers and the addition of 20 vol% DMSO is useful to enhance both the solubility of aromatic substrates and products and the stability of BAL. The initial broad product range of BAL-catalyzed reactions has been enlarged to include highly substituted hydroxybutyrophenones and aliphatic acyloins.
Janzen
Elena
E
Institute of Enzyme Technology, Heinrich-Heine University Duesseldorf, Research Centre Juelich, 52426 Juelich, Germany.
Müller
Michael
M
Kolter-Jung
Doris
D
Kneen
Malea M
MM
McLeish
Michael J
MJ
Pohl
Martina
M
D000446:Aldehyde-Lyases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D002021:Buffers; D002384:Catalysis; D003001:Cloning, Molecular; D004795:Enzyme Stability; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D009154:Mutation; D011551:Pseudomonas fluorescens / Q000201:enzymology*; D012997:Solvents; D013696:Temperature
D002021:Buffers; D012997:Solvents; D000446:Aldehyde-Lyases; C059416:benzaldehyde lyase