Determination of the concentration of active sites and the catalytic rate constant of recombinant formate dehydrogenase from <Emphasis Type="Italic">Glycine max</Emphasis>

The analysis of a formate dehydrogenase (FDH) structure in the apo form and in a complex with nicotinamide (NAD⁺) and azide ion has shown a high probability of efficient fluorescence quenching during the formation of such a triple complex. The excitation and fluorescence spectra indicated that the enzyme fluorescence is determined by tryptophan residues. The dependence of FDH fluorescence quenching on the NAD⁺ and azide concentrations was studied. The obtained data were used to determine the concentration of active sites and the catalytic rate constant of recombinant FDH from Glycine max.