University of Natural Resources and Life Sciences, Vienna (BOKU) - Research portal

Logo BOKU Resarch Portal

Selected Publication:

Breslmayr, E; Poliak, P; Pozgajcic, A; Schindler, R; Kracher, D; Oostenbrink, C; Ludwig, R.
(2022): Inhibition of the Peroxygenase Lytic Polysaccharide Monooxygenase by Carboxylic Acids and Amino Acids
ANTIOXIDANTS-BASEL. 2022; 11(6), 1096 FullText FullText_BOKU

Lytic polysaccharide monooxygenases (LPMOs) are widely distributed in fungi, and catalyze the oxidative degradation of polysaccharides such as cellulose. Despite their name, LPMOs possess a dominant peroxygenase activity that is reflected in high turnover numbers but also causes deactivation. We report on the influence of small molecules and ions on the activity and stability of LPMO during catalysis. Turbidimetric and photometric assays were used to identify LPMO inhibitors and measure their inhibitory effect. Selected inhibitors were employed to study LPMO activity and stability during cellulose depolymerization by HPLC and turbidimetry. It was found that the fungal metabolic products oxalic acid and citric acid strongly reduce LPMO activity, but also protect the enzyme from deactivation. QM calculations showed that the copper atom in the catalytic site could be ligated by bi- or tridentate chelating compounds, which replace two water molecules. MD simulations and QM calculations show that the most likely inhibition pattern is the competition between the inhibitor and reducing agent in the oxidized Cu(II) state. A correlation between the complexation energy and the IC50 values demonstrates that small, bidentate molecules interact strongest with the catalytic site copper and could be used by the fungus as physiological effectors to regulate LPMO activity.
Authors BOKU Wien:
Breslmayr Erik
Kracher Daniel
Ludwig Roland
Oostenbrink Chris
Poliak Peter
BOKU Gendermonitor:

Find related publications in this database (Keywords)
density functional theory
lytic polysaccharide
molecular dynamics simulations
quantum mechanical calculations

© BOKU Wien Imprint