Interaction of amine oxides and quaternary ammonium salts with membrane and membrane-associated processes in E. coli cells: mode of action.
The antimicrobials (1-methyldodecyl)dimethylamine oxide and (1-methyldodecyl)trimethylammonium bromide affect the cytoplasmic membrane of E. coli. The interaction results in release of intracellular material (K+, 260nm-absorbing material), an effect on dehydrogenase enzyme activity and inhibition of respiration. The final effect of both substances is the same; they differ only in their dynamics. The effect of the membrane was correlated with parameters characterizing these surfactants i.e. critical micelle concentration (c.m.c.) minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) over the concentration range of 10(-4) to 10(-1) mmol/dm3 of active substance. The three stage mode of action model can be summarized as follows: 1-polar (coulombic) interactions, 2-polar and hydrophobic interactions, 3-hydrophobic interactions (extraction and solubilization). The polar and hydrophobic interactions (1st and 2nd stage) are discussed also in relation to model membranes.
Kopecká-Leitmanová
A
A
Faculty of Pharmacy, Komensky University, Bratislava, Czechoslovakia.
Devínsky
F
F
Mlynarcik
D
D
Lacko
I
I
D002462:Cell Membrane / Q000187:drug effects*; D002463:Cell Membrane Permeability / Q000187:drug effects; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003470:Culture Media; D004926:Escherichia coli / Q000187:drug effects* / Q000648:ultrastructure; D008744:Methylamines / Q000138:chemical synthesis / Q000494:pharmacology*; D008823:Micelles; D008826:Microbial Sensitivity Tests; D009391:Nephelometry and Turbidimetry; D010088:Oxidoreductases / Q000378:metabolism; D010101:Oxygen Consumption / Q000187:drug effects; D000644:Quaternary Ammonium Compounds / Q000138:chemical synthesis / Q000494:pharmacology*; D013055:Spectrophotometry, Infrared; D013500:Surface Tension
D003470:Culture Media; D008744:Methylamines; D008823:Micelles; D000644:Quaternary Ammonium Compounds; D010088:Oxidoreductases; C005855:trimethyloxamine; C027917:tetramethylammonium