MAGNESIUM UPTAKE BY SPHAEROTILUS-NATANS - THE INHIBITING EFFECT OF ETHANOL

Aim of the present paper is to give a contribution for a(~)better understanding of the mechanism of magnesium accumulation by cells of Sphaerotilus natans. The results presented in this paper seem to confirm the non strictly biological nature of the phenomenon. An inhibiting effect of ethanol on the uptake is also evidenced and a hypothesis for the inhibition mechanism, implying the simultaneous occurrence of both physical and biological phenomena, is presented. In the presence of ethanol a film around the cell membrane is likely to be produced, partially preventing the adhesion of magnesium ions on the wall; subsequently, ethanol would be transformed into acetic acid and magnesium removed from the cell wall as a salt. All the efforts to improve the process yields and the resistance of the microorganism to ethanol, through specific adaptions, have not given the expected results. List of symbols(~)[GRAPHICS]