摘要
应用［１４Ｃ］－青霉素对５０株铜绿假单胞菌进行了青霉素结合蛋白亲和力及与膜通透性、β-内酰胺酶、药物敏感性间关系的研究，并对液闪同位素计数法测定青霉素蛋白结合率进行了尝试。结果表明：①亚胺培能对铜绿假单胞菌的致死靶位蛋白为ＰＢＰｓ２。②铜绿假单胞菌临床分离株对亚胺培能耐药率达１４％；所有敏感株的膜通透率（３５．０％）与ＰＢＰｓ结合率（４６．５８％）均高于耐药株（２３．６１％、３４．５０％，Ｐ＜０．０５）。③耐药株中高产酶株（ ～ ）可达２８．５９％远高于敏感株１３．９５％（Ｐ＜０．０１），其β－内酰胺酶产酶量越高则膜通透率及ＰＢＰｓ结合率越低。④无论膜通透率是０还是１００％，ＰＢＰｓ结合率无明显改变。结果提示：耐碳青烯类抗生素的铜绿假单胞菌，其耐药机制是多方面的，主要与细菌膜通透性改变及β-内酰胺酶水解有关，而与ＰＢＰｓ无关。
The affinity of imipenem for penicilline-binding proteins of Pseudomonas aeruginosa was stud- ied. By using C14-penicilline and liquid-scintillant isotope counting assay, the penicilline-binding proteins of P. aeruginosa for imipenem were detected and their relationships with permeability of outer membrane and β-lacta- mase in the sensitivity of antibiotics to P. aeruginosa were investigated. Results showed that imipenem could kill P. aeraginosa by the target of PBPs2; The resistant rate of imipenem to P. aeruginosa was up to 14 %; The permeability rate (35 % ) and PBPs binding rate (46. 58 %) in the sensitive strains were higher than that, 28.59 % and 13. 95 %, in the resistant strains (P<0. 05), respectively. The resistant strains produced much more β-lactamase than the sensitive strains, and the amount of β－lactamase was increased with lower permeabili- ty rate and Penicilline-binding rate. PBPs binding rate had no change with permeabitity rate being 0 or 100 %. It was suggested that the resistant mechanism of P. aeruginosa to imipenem might be involved mostly in the permeability of outer membrane Of P. aeruginosa and its β-lactamase's hydrolysis, but not in PBPs itself.
出处
《同济医科大学学报》
CSCD
2000年第6期522-525,共4页
Acta Universitatis Medicinae Tongji
基金
国家自然科学基金资助项目(No.39570846)
关键词
铜绿假单胞菌
青霉素结合蛋白
亚胺培能
pseudomonas aeruginosa
β-lactamase
outer membrane
permeability
