Abstract

ECHAND, Karina  and  HERNANDEZ, Francisco. Alteraciones ultraestructurales en la pared celular de pseudomonas aeruginosa inducidas por amikacina. Rev. costarric. cienc. méd [online]. 1997, vol.18, n.4, pp.51-55. ISSN 0253-2948.

The aminoglycosides were introduced with streptomycin en 1944, today this group of antibiotics includes natural and semisynthetic drugs, such as amikacin sulfate, used for treating Pseudomonas aeruginosa infections. The best known action of this antibiotic is the inhibition of bacterial protein synthesis; nevertheless, its bactericidal activity is associated with its interactions and destabilization of the outer membrane.     Pseudomonas aeruginosa (strain ATCC 27853) was treated in vitro with amikacin and as control, the strain was inoculated in culture media without antibiotic. The bacteria were harvested and suspended in cacodilate buffer and fixed with a mixture of 2.5% glutaraldehide, 0.075% ruthenium red, and 50mM lysine, and processed for electron microscopy.     The bacteria treated with the antibiotic showed a wavier outer membrane than the controls and the cell wall of the bacteria exposed to the antibiotic was altered; also, their cytoplasm showed clear zones, like vacuoles, but without membranes and the remaining cytoplasm was more electrondense than the cytoplasm of the untreated control cells.

Keywords : Ultrastructure; Pseudomonas aeruginosa; amikacin; cell wall.