TY  - JOUR
A1  - Laun, Konstantin
A1  - Duffus, Benjamin R.
A1  - Wahlefeld, Stefan
A1  - Katz, Sagie
A1  - Belger, Dennis Heinz
A1  - Hildebrandt, Peter
A1  - Mroginski, Maria Andrea
A1  - Leimkühler, Silke
A1  - Zebger, Ingo
T1  - Infrared spectroscopy flucidates the inhibitor binding sites in a metal-dependent formate dehydrogenase
JF  - Chemistry - a European journal
N2  - Biological carbon dioxide (CO2) reduction is an important step by which organisms form valuable energy-richer molecules required for further metabolic processes. The Mo-dependent formate dehydrogenase (FDH) from Rhodobacter capsulatus catalyzes reversible formate oxidation to CO2 at a bis-molybdopterin guanine dinucleotide (bis-MGD) cofactor. To elucidate potential substrate binding sites relevant for the mechanism, we studied herein the interaction with the inhibitory molecules azide and cyanate, which are isoelectronic to CO2 and charged as formate. We employed infrared (IR) spectroscopy in combination with density functional theory (DFT) and inhibition kinetics. One distinct inhibitory molecule was found to bind to either a non-competitive or a competitive binding site in the secondary coordination sphere of the active site. Site-directed mutagenesis of key amino acid residues in the vicinity of the bis-MGD cofactor revealed changes in both non-competitive and competitive binding, whereby the inhibitor is in case of the latter interaction presumably bound between the cofactor and the adjacent Arg587.
KW  - CO2 reduction
KW  - DFT
KW  - formate oxidation
KW  - inhibition kinetics
KW  - IR
KW  - spectroscopy
KW  - molybdoenzyme
Y1  - 2022
U6  - https://doi.org/10.1002/chem.202201091
SN  - 0947-6539
SN  - 1521-3765
PB  - Wiley-VCH
CY  - Weinheim
ER  -