Program

O.9 -- Oral, IWTCP-3

Date: Wednesday, 29 July 2015

Time: 16h35 - 16h55

Molecular Modelling of Alcohol Dehydrogenase from Lactobacillus Brevis in Organic Solvent

Quy Vo (1), Jan-Hendrik Grosch (2), Antje Spiess (2), Juergen Pleiss (1)

(1) Institute of Technical Biochemistry, University of Stuttgart, Stuttgart, Germany; (2) Enzyme Process Technology, RWTH Aachen, Aachen, Germany

Alcohol dehydrogenases from Lactobacillus brevis (LbADH, EC 1.1.1.2) is a widely used biocatalyst due to its high catalytic activity towards a broad range of substrates and its high tolerance towards non-conventional media. To investigate the structural and functional determinants of stability and activity in organic solvents, molecular dynamics simulations of a ternary complex of LbADH, NAD/NADH, and Mg2+ were performed in mixtures of an organic solvent, diisopropyl ether, and water. The simulation in organic solvent was compared to simulations in pure water. The simulation results are consistent with experimental data: LbADH is stable in pure water and in the organic solvent. The enzyme is more rigid in the organic solvent than in pure water. Interestingly, the binding of functional water molecules in the binding pocket is disturbed by diisopropyl ether. In organic solvent, water molecules that are crucial for the proton relay system are withdrawn from the binding pocket, which implies that the effect of organic solvent is a dominant factor for the enzymatic activity.

Presenter: Quy Cam Vo