Diffusion of aminoglycoside antibiotics across the outer membrane of Escherichia coli.
AUTOR(ES)
Nakae, R
RESUMO
The diffusion of aminoglycoside antibiotics (gentamicin, kanamycin, streptomycin, fradiomycin, lividomycin, and mannosylparomomycin) through porin pores was examined in vitro by the liposome swelling technique, using vesicle membranes reconstituted from phospholipids and purified porin trimers. Results showed that aminoglycoside antibiotics diffuse through porin-pores very efficiently, as rapidly as hexoses and disaccharides, despite the fact that the molecular weights of the aminoglycosides used were higher than or close to the exclusion limit of porin pores. The susceptibility to aminoglycoside antibiotics of mutant strains producing 3 to 4% of porin was not significantly different from that of a strain producing a wild-type quantity of porin. These results were interpreted to mean that aminoglycoside antibiotics diffuse through porin-pores very efficiently. Therefore, the diffusion of these drugs through the mutant outer membranes producing 3 to 4% of porin is not a rate-limiting step for aminoglycoside diffusion and its action.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=183792Documentos Relacionados
- Translocation of a folded protein across the outer membrane in Escherichia coli.
- Conversion of the FhuA transport protein into a diffusion channel through the outer membrane of Escherichia coli.
- Binding of metallic ions to the outer membrane of Escherichia coli.
- Regulation of the OmpA outer membrane protein of Escherichia coli.
- Localization of proteolytic activity in the outer membrane of Escherichia coli.