头孢噻肟钠与重金属对AmpC β-内酰胺酶类抗性基因转移的影响

发布时间：2018-06-03 16:07

本文选题：抗性基因 + 大肠杆菌　；参考：《环境科学学报》2017年09期

【摘要】：为探究抗生素和重金属对抗性转移及接合子抗性基因丰度的影响,借助绿色荧光蛋白标记质粒,采用滤膜接合配对方法研究了胁迫条件对细菌接合频率的影响,定量检测了转移后的AmpC β-内酰胺酶类抗性基因丰度的变化.结果表明,头孢噻肟钠及重金属共胁迫促进了AmpC β-内酰胺酶类抗性基因从复杂群落到Escherichia coli BL21的转移.3μg·L~(-1)头孢噻肟钠胁迫下,细菌接合频率为空白组的2.06倍,其中,接合子耐药基因CIT、FOX和EBC的相对丰度分别升高了7.47、4.30和1.60倍.同时,以3μg·L~(-1)头孢噻肟钠胁迫组为对照,研究了重金属汞、铜和锌共胁迫对抗性转移的影响,考虑到头孢噻肟钠的水解特性和接合子克隆性扩增,接合时间定为3 h.结果发现,汞、铜、锌与头孢噻肟钠共胁迫组的细菌接合频率分别比对照组增长了2.57、1.60和1.74倍.汞共胁迫对接合子中7种AmpC β-内酰胺酶类抗性基因丰度无显著影响;铜共胁迫效应因抗生素抗性基因(ARGs)种类不同而不同,其中,对抗性基因EBC相对丰度的影响最大;锌共胁迫效应受锌离子浓度和ARGs种类影响,100 mg·L~(-1)锌共胁迫使得EBC和CIT丰度比对照组分别增加3.56和2.76倍.可见,抗生素与重金属共胁迫条件可促进环境中AmpC β-内酰胺酶类抗性基因的转移,值得关注.
[Abstract]:In order to explore the effects of antibiotics and heavy metals on resistance to sexual transfer and the abundance of zygote resistance genes, the effects of stress conditions on the bacterial conjugation frequency were studied by the method of green fluorescent protein labeling plasmids. The changes of the resistance gene abundances of AmpC beta lactamases after the transfer were quantified. Cyclosporine sodium and heavy metal co stress promoted the AmpC beta lactamase resistance gene from complex community to Escherichia coli BL21 transfer.3 mu g. L~ (-1) cefotaxime sodium stress, the bacterial conjugation frequency was 2.06 times that of the blank group, of which the conjugant resistance gene CIT, FOX and EBC increased the 7.47,4.30 and 1.60 times respectively. At the time, the effects of heavy metal mercury, copper and zinc co stress on antagonistic metastasis were studied with 3 g / L~ (-1) cefotaxime sodium stress group. Considering the hydrolysis characteristics of cefotaxime sodium and clonogenic amplification of zygote, the conjugation time was 3 h., and the bacterial conjugation frequency of mercury, copper, zinc and cefotaxime co stress group was compared to the control The group was increased by 2.57,1.60 and 1.74 times. The abundances of 7 kinds of AmpC beta lactamases in the zygote were not significantly affected, and the Copper Co stress effect was different because of the variety of antibiotic resistance gene (ARGs), among which the relative abundance of the antagonistic gene EBC was the most. The zinc Co stress effect was influenced by the concentration of zinc ions and the type of ARGs, 100 mg / L~ (-1) zinc co stress increased the abundance of EBC and CIT by 3.56 and 2.76 times respectively. The co stress conditions of antibiotics and heavy metals can promote the transfer of AmpC beta lactamase resistance genes in the environment, which is worth paying attention to.
【作者单位】：广东工业大学环境科学与工程学院;
【基金】：国家自然科学基金(No.41671481) 广东省应用型科技研发专项资金项目(No.2016B020240003)~~
【分类号】：X172

【相似文献】