【摘要】 目的检测铜绿假单胞菌生物被膜(Biofilm, BF)中AmpC酶和超广谱β-内酰胺酶(Extend-ed-Spectrumβ-Lactamases, ESBLs)的产生率,并观察其对耐药性的影响。方法用改良平板培养法在硅胶膜上建立铜绿假单胞菌BF的体外模型。用银染法及扫描电镜对BF进行鉴定。应用琼脂稀释法测定最低抑菌浓度(MIC)。应用三维试验检测AmpC酶和ESBLs,等电聚焦电泳测定β-内酰胺酶的等电点。结果50株铜绿假单胞菌BF中AmpC酶的产生率为82.0%(41/50),ESBL的产生率为16.0%(8/50),AmpC酶和ESBLs均阳性的占10.0%(5/50),AmpC酶和ESBL均阴性的占12.0%(6/50)。浮游组中AmpC酶的产生率为60.0%(30/50),ESBLs的产生率为14.0%(7/50),AmpC酶和ESBL均阳性的占8.0%(4/50),AmpC酶和ESBLs均阴性的占34.0%(17/50)。结论生物被膜铜绿假单胞菌的耐药性与其中β-内酰胺酶的产生,尤其是AmpC酶的产生有关。更多还原

【Abstract】 Objective:To study the producing of ESBLs from Klebsiella pneumonia,Escherichia coli and Pseudomonas aeruginosa biofilm bacteria.Methods:In vitro models of Klebsiella Pneumoniae,Escherichia coli and Pseudomonas aeruginosa bacterial bioflim were set up in silicon disk with the modified plating method and a rapid staining procedure of AgNO3was used to confirm them.We observed biofilms under scanning electron microscope.The experiment was divided into six groups.Group A1and A2were planktonic bacteria and biofilm of Klebsiella pneumonia respectively.Group B1and B2were planktonic and biofilm of Es-cherichia coli,Group C1and C2were planktonic and biofilm of Pseudomonas aeruginosa respectively.Dou-ble-disk synergy test was used to detect ESBLs-producing strains,and the isoelectric point(pI)ofβ-lacta-mase was quantitated by isoelectrofocusing eletrophoresis.Results:The isolation rate of ESBLs-producing strain in biofilm of Klebsiella pneumoniae,Escherichia coli and Pseudomonas aeruginosa were46.7%(14/30),33.3%(10/30)and10%(3/30),respectively.The isolation rates of group A1and A2,group B1and B2were different from each other significantly with the statistic method ofχ2-test(P<0.05).Theβ-lactamase with pI7.6was the major ESBLs,followed by pI8.2.Conclusions:Isolation rate of ESBLs-producing Klebsiella pnu-moniae in biofilm was higher than the others,and the major ESBLs was SHV type.更多还原