Enzyme Responses to Low and Very Low Doses of Effectors. Review and New Facts

This review systematises studies on changes in oxidoreductase activity triggered by high dilutions of their phenolic effectors. The studies focused primarily on fungal and plant peroxidases, fungal laccases, and veratric acid O-demethylases from soil bacteria. A common feature of the above studies was the demonstration of oscillatory changes in the activity of the tested enzymes as effectors are progressively diluted. The pattern of these oscillations was unique for the enzyme/effector complex, providing practical information regarding the allosteric adaptation of this complex. Oscillatory changes in enzyme activity were also accompanied by equivalent changes in cell numbers in bacterial cultures and in their morphological differentiation. The review of experimental studies revealed that information from low and very low doses of effectors influenced the entire metabolic pathways of the tested organisms. The repeatability of the results was ensured by using a unified system for preparing dynamic dilutions of effectors in aqueous or alcoholic solutions.