The influence of pH and divalent/monovalent cations on the internal electron transfer (IET), enzymatic activity, and structure of fructose dehydrogenase.

ABSTRACT: We report on the influence of pH and monovalent/divalent cations on the catalytic current response, internal electron transfer (IET), and structure of fructose dehydrogenase (FDH) by using amperometry, spectrophotometry, and circular dichroism (CD). Amperometric measurements were performed on graphite electrodes, onto which FDH was adsorbed and the effect on the response current to fructose was investigated when varying the pH and the concentrations of divalent/monovalent cations in the contacting buffer. In the presence of 10 mM CaCl₂, a current increase of up to ≈ 240% was observed, probably due to an intra-complexation reaction between Ca²⁺ and the aspartate/glutamate residues found at the interface between the dehydrogenase domain and the cytochrome domain of FDH.

SUBMITTER: Bollella P 

PROVIDER: S-EPMC5937911 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature