Mechanism insights into the changes in activity and structure of cellular alcohol dehydrogenase in Acetobacter sp. after pulsed electric fields treatment

Abstract

Pulsed electric fields (PEF) can affect enzyme activity in fruit and vegetable juice, but its effect on microbial cellular enzymes has not been fully revealed. Alcohol dehydrogenase (ADH) is a key cellular enzyme of Acetobacter sp. to convert alcohol to acetic acid by metabolism. In this study, the effect of PEF treatment on the ADH activity of Acetobacter sp. and the structural changes of the enzyme were systematically investigated. The results showed that the activity of cellular ADH in Acetobacter sp. was decreased by PEF treatment. The α-helix structure of ADH molecules decreased and the random coil structure increased, indicating a change in secondary structure. The tertiary structure of ADH was expanded and the microenvironment of aromatic amino acid residues was changed, while the primary structure of molecules remained intact. In conclusion, the decrease of ADH activity after PEF treatment may be caused by the transformation of spatial conformation.