Effect of chlorhexidine diacetate on “protoplasts” and spheroplasts of Escherichia coli, protoplasts of Bacillus megaterium and the Gram staining reaction of Staphylococcus aureus

Abstract

Abstract Chlorhexidine prevents the transformation of Bacillus megaterium cells to protoplasts by lysozyme, of E. coli cells to spheroplasts by penicillin and causes lysis of “protoplasts” and spheroplasts of E. coli stabilised in hypertonic sucrose solution. Transformation of Staphylococcus aureus cells to the Gram-negative condition occurred in contact with 10 to 800 μg/ml of chlorhexidine and 10, 50 and 100 μg/ml of cetyltrimethylammonium bromide but higher concentrations of the latter prevented this change. Results indicate that chlorhexidine damages the permeability barrier of bacterial cells.