Bacterial Resistance to Quaternary Ammonium Disinfectants

Abstract

The occurrence of acquired drug resistance in bacteria is now a familiar phenomenon and gives rise to serious problems in disinfection and in chemotherapy. It has been a matter of conjecture whether a strain giving rise to resistant progeny originally lacked homogeneity in respect of its drug susceptibility, or whether its enhanced resistance is a result of a direct chemical response of its biochemical processes. It has been shown recently (Chaplin, 1951) that certain bacterial species are capable of acquiring a great degree of resistance to the action of quatemary ammonium disinfectants, and at the same time it was shown that the strains used were definitely not homogeneous in susceptibility. It is a reasonable supposition, considering the supposed mode of action and the extreme surface activity of these compounds, that a profound change must be wrought in the cell surface during the acquisition of resistance. It is with the nature of this change

Lipid Content of Antibiotic-Resistant and -Sensitive Strains of Serratia marcescens

“…In recent years, the structure and function of the relationship of cell wall components to bacterial antibiotic resistance have been studied extensively (24). Studies by a number of investigators (5,6,19) have suggested that increased synthesis of lipid may be a factor in the resistance of bacteria to antibacterial substances (2,5,6,19,27). More recently, the alteration of fatty acid composition of gramnegative bacteria was noted as a consequence of antibiotic resistance (9).…”

Ultrastructural Alterations Associated with the Growth of Resistant Pseudomonas aeruginosa in the Presence of Benzalkonium Chloride

“…However, cell envelopes of the BC-sensitive parent strain contained only 15% readily extractable lipids (Adair, Geftic, Heymann, unpublished data). Cationic quaternary ammonium compounds also bind strongly to the cell surfaces of sensitive and resistant strains (9,17), thus neutralizing the net negative charge of the cells (18). Consequently, it was not unexpected to find that BC-grown resistant cells had staining properties different from those of the sensitive strain.…”

The Biological Actions of 1,10‐phenanthroline and 2,2′‐bipyridine Hydrochlorides, Quaternary Salts and Metal Chelates and Related Compounds

“…It is also typical of the lack of resistance shown by a variety of organisms to other types of cationic antibacterials (Newton, 1958;Hugo, 1967). It has been reported tliat resistance of certain bacteria to quaternary ammonium and related compounds may be accompanied by increased synthe.sis of surface glycolipid or proteolipid (Chaplin, ,1952;Hugo, 1967) which would permit greater surface binding of cation and thus decrease the concentration reaching more vital membrane or intracellular sites. In these circumstances, the natural resistance of the Cram-negative bacteria to the metal chelates and quaternary salts may be due to the high polar Hpid content of their cell walls.…”