阿奇霉素上调生物被膜阳性铜绿假单胞菌Ⅰ类整合酶基因的表达

Azithromycin up-regulated classⅠ integron-integrase gene expression in biofilm-forming Pseudomonas aeruginosa

目的探讨阿奇霉素对生物被膜(BF)阳性铜绿假单胞菌(PA)Ⅰ类整合酶基因(intI1)mRNA表达量的影响。方法对某院临床分离的10株PA进行intI1基因检测,选择其中1株BF+intI1基因阳性的PA进行培养,并设空白对照组和阿奇霉素处理组(按阿奇霉素浓度不同分为3个浓度组,分别为16、32、64 mg/L组),重复试验5次,采用荧光定量聚合酶链式反应(RT-PCR)检测其intI1 mRNA的表达情况。结果16 mg/L阿奇霉素组、32 mg/L阿奇霉素组、64 mg/L阿奇霉素组和对照组intI1 mRNA相对表达量分别为(1.15±0.04)、(12.47±3.10)、(19.71±0.78)和(1.00±0.00),各组间比较,差异有统计学意义(F=163.82,P<0.001);组间两两比较,除低浓度阿奇霉素组(16 mg/L)与对照组比较,差异无统计学意义(P>0.05)外,其他各组间比较,差异均有统计学意义(P<0.05),阿奇霉素组intI1 mRNA表达量随培养液中阿奇霉素浓度升高而升高。结论在阿奇霉素压力下BF阳性的PA,intI1表达有所上调,可提高耐药基因的捕获概率,促进耐药基因重组。

Objective To evaluate the effect of azithromycin on class Ⅰ integron-integrase gene （intI 1 ）mRNA expression in biofilm-forming （BF）Pseudomonas aeruginosa （PA）.Methods intI 1 of 10 PA strains isolated from a hospital were detected,1 strain with positive BF＋intI 1 was selected for culture,blank control group and three az-ithromycin trial groups （divided according to 3 concentrations：16 mg/L,32 mg/L,and 64 mg/L）were set,experi-ments were repeated 5 times,expression of intI 1 mRNA were detected by RT-PCR.Results Relative expression of intI 1 mRNA in azithromycin groups of 16 mg/L,32 mg/L,64 mg/L,and control group were （1 .15 ±0.04）, （12.47±3.10）,（19.71 ±0.78 ）,and （1 .00 ±0.00）,respectively,there were significant difference among four groups（F =163.82,P 〈0.001 ）;intI 1 mRNA expression between 16mg/L azithromycin group and control group was not significantly different （P 〉0.05）,but among other groups were significantly different （P 〈0.05 ）,intI 1 mRNA expression in azithromycin groups increased with the enhancing concentration of azithromycin in culture so-lution .Conclusion Expression of intI 1 gene mRNA in BF PA can be up-regulated by the present of azithromycin, which may improve the probability of drug-resistant genes,and promote drug-resistant gene recombination.