title: Mechanism of resistance to benzalkonium chloride by Pseudomonas aeruginosa.
abstract: The mechanisms of resistance of Pseudomonas aeruginosa to benzalkonium chloride (BC) were studied. The effluence of cell components was observed in susceptible P. aeruginosa by electron microscopy, but resistant P. aeruginosa seemed to be undamaged. No marked changes in cell surface potential between Escherichia coli NIHJC-2 and a spheroplast strain were found. The contents of phospholipids (PL) and fatty and neutral lipids (FNL) in the cell walls of resistant P. aeruginosa were higher than those in the cell walls of susceptible P. aeruginosa. The amounts of BC adsorbed to PL and FNL of cell walls of BC-resistant P. aeruginosa were lower than those for BC-susceptible P. aeruginosa. Fifteen species of cellular fatty acids were identified by capillary gas chromatography and gas chromatography-mass spectrometry. The ability of BC to permeate the cell wall was reduced because of the increase in cellular fatty acids. These results suggested that the resistance of P. aeruginosa to BC is mainly a result of increased in the contents of PL and FNL. In resistant P. aeruginosa, the decrease in the amount of BC adsorbed is likely to be the result of increases in the contents of PL and FNL.
authors.affiliation: Osaka Prefectural Institute of Public Health, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Sakagami
authors.forename: H
authors.initials: H
authors.lastname: Yokoyama
authors.forename: H
authors.initials: H
authors.lastname: Nishimura
authors.forename: Y
authors.initials: Y
authors.lastname: Ose
authors.forename: T
authors.initials: T
authors.lastname: Tashima
mesh_terms: D001548:Benzalkonium Compounds / Q000494:pharmacology*; D002473:Cell Wall / Q000032:analysis; D002849:Chromatography, Gas; D004352:Drug Resistance, Microbial; D004926:Escherichia coli / Q000187:drug effects; D008401:Gas Chromatography-Mass Spectrometry; D008564:Membrane Potentials; D008854:Microscopy, Electron; D010743:Phospholipids / Q000032:analysis; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure
chemical_list: D001548:Benzalkonium Compounds; D010743:Phospholipids