摘要
To study the resistant mechanism and clinical significance of pseudomonas aeruginosa toβ- lactam antibiotics,the outer mem brane permeability rate of30 P.aeruginosa strains to5 β- lactam antibiotics was m easured and their production ofβ- lactamase and theβ- lactam ase genes they carried detected. Furthermore,the relationship between the perm eability,β- lactam ase and the clinical effects ofβ- lactam antibiotics was observed. By using 1 4C- penicillin and liquid- scintillant isotope assay,the affinity of penicillin binding proteins(PBPs) was m easured and their roles in the resistant m echanism studied.Itwas revealed thatthe perm eability rate was higher in sensitive strains than in resistantones(P<0 .0 5 ) .All strains harbored1- 4 β- lactamase genes and produced β- lactam ase.Higher permeability rate and higher degree of stability toβ- lactamase indicated better clinical therapeutic effects. The affinity of PBPs changed little without regard to the perm eability andβ- lactam ase. These results suggested that the permeability of outer mem brane andβ- lacta- mase,but not PBPs,played im portant roles in the resistant mechanism of P. aeruginosa toβ- lac- tam antibiotics and affected the clinical therapeutic effectiveness of som e patients.
To study the resistant mechanism and clinical significance of pseudomonas aeruginosa toβ- lactam antibiotics,the outer mem brane permeability rate of30 P.aeruginosa strains to5 β- lactam antibiotics was m easured and their production ofβ- lactamase and theβ- lactam ase genes they carried detected. Furthermore,the relationship between the perm eability,β- lactam ase and the clinical effects ofβ- lactam antibiotics was observed. By using 1 4C- penicillin and liquid- scintillant isotope assay,the affinity of penicillin binding proteins(PBPs) was m easured and their roles in the resistant m echanism studied.Itwas revealed thatthe perm eability rate was higher in sensitive strains than in resistantones(P<0 .0 5 ) .All strains harbored1- 4 β- lactamase genes and produced β- lactam ase.Higher permeability rate and higher degree of stability toβ- lactamase indicated better clinical therapeutic effects. The affinity of PBPs changed little without regard to the perm eability andβ- lactam ase. These results suggested that the permeability of outer mem brane andβ- lacta- mase,but not PBPs,played im portant roles in the resistant mechanism of P. aeruginosa toβ- lac- tam antibiotics and affected the clinical therapeutic effectiveness of som e patients.
基金
This project was supported by a grant from Natural Sci-ences Foundation of China(No. 395 70 84 6 )
