[Effect of cell wall polyphosphates on the sensitivity of the yeast Saccharomyces carlsbergensis to the damaging action of cetyltrimethylammonium bromide].

The effect of cetyltrimethylammonium bromide (CTAB) on Saccharomyces carlsbergensis cells grown in orthophosphate-containing medium and on cells starved of phosphorus was studied by electroorientation spectroscopy. CTAB (20 microM) was found to substantially damage the plasma membrane (PM)) of cells grown in the presence of orthophosphate, while cells starved of phosphorus were damaged to a lesser extent. Biochemical analysis of the content of inorganic polyphosphate (poly(P(i))) in the cells, as study of their capacity to adsorb 9-aminoacridine, a fluorescent cationic dye, suggested that the different sensitivity of the plasma membrane to CTAB was due to differences in the content of polyanionic molecules of poly(P(i)) in the cell wall and consequent differences in its net negative charge. Magnesium cations increased the time of CTAB penetration through the cell wall and reduced the damage inflicted on the PM.