RESUMO
AIMS: To study the effect of diethylsulphoxide (DESO) on Escherichia coli growth, survival and ionic exchange in comparison with dimethylsulphoxide (DMSO). METHODS AND RESULTS: Bacterial survival was estimated by counting colony-forming units and by the most probable number (five-tube) technique; the K+ and H+ transport and H(2) formation were determined electrochemically. Diethylsulphoxide at concentrations between 0.01 and 0.5% (w/v) stimulated and above 5% decreased the anaerobic growth rate and survival. 2H+ : K+ exchange and H(2) formation were lost at 5% DESO. At 0.05% DESO the kinetic characteristics of H+ : K+ exchange and H(2) formation were typical for Delta micro (H(+)) -dependent TrkA uncoupled with F(0)F(1) under respiration. CONCLUSIONS: Diethylsulphoxide at low concentrations serves as an electron acceptor for an anaerobic respiratory chain stimulating bacterial growth and survival through the modulation of H+ : K+ exchange and H(2) formation activity. The effects of DESO were more pronounced than those of DMSO. SIGNIFICANCE AND IMPACT OF THE STUDY: Diethylsulphoxide determines essential biological and therapeutic properties that make its application preferable.
