Kinetic Modeling of Acetophenone Reduction Catalyzed by Alcohol Dehydrogenase from Thermoanaerobacter sp.

Abstract

NADPH-dependent alcohol dehydrogenase (ADH) from Thermoanaerobacter sp. was kinetically characterized using reduction of acetophenone as a model. To achieve 98% conversion of acetophenone, cofactor regeneration by oxidation of 2-propanol with the same enzyme was used. The enzyme was stable in the batch reactor. It was enantioselective towards (S)-1-phenylethanol (ee>99.5%). Due to its high deactivation in continuously operated stirred tank reactor (kd=0.0141 min-1) there was no way to keep high conversion of acetophenone at 98%. The deactivation occurred in the repetitive batch as well. A mathematical model for the acetophenone reduction with cofactor regeneration describing the behaviour in a batch, repetitive-batch and continuously stirred tank reactor was developed.

Combining Designer Cells and Click Chemistry for a One‐Pot Four‐Step Preparation of Enantiopure β‐Hydroxytriazoles

“…The first construct (CT cells) expressed AdhT, an R-selective alcohol dehydrogenase from Thermoanaerobacter sp. [13] and HheC, the R-selective halohydrin dehalogenase from Agrobacterium radiobacter AD1. [14] The second type of cells (BL cells) expressed AdhL, the S-selective alcohol dehydrogenase from Lactobacillus brevis [15] and HheBGP1, the halohydrin dehalogenase from Mycobacterium sp.…”

Promiscuous Substrate Binding Explains the Enzymatic Stereo‐ and Regiocontrolled Synthesis of Enantiopure Hydroxy Ketones and Diols

“…Lactobacillus brevis ADH (LBADH), [44] alcohol dehydrogenase from Rhodococcus ruber (ADH-'A'), [45] and ADH from Thermoanaerobacter sp. (ADH-T) [46] were selected as biocatalysts to perform the corresponding reductions using an excess of 2-propanol as hydrogen donor, through a 'substrate-coupled' or 'biocatalytic hydrogen transfer' approach. [14] The first enzyme shows a perfect anti-Prelog selectivity, this is, it catalyses the transfer of the hydride to the carbonyl moiety through its si face, while the second and third ADHs display an excellent Prelog profile.…”

Enzyme kinetic modelling and analytical solution of nonlinear rate equation in the transformation of D-methionine into L-methionine in batch reactor using the new homotopy perturbation method

“…Therefore, the subject of this study is focused on the kinetics of the oxidative deamination, a very complex reaction system, which is catalyzed by D-AAO from Arthrobacter protophormiae using its natural substrate D-methionine and the aromatic amino acid 3,4-dihydroxyphenyl-D-alanine (D-DOPA). [13][14][15] Findrik et. al.…”