摘要

人们越来越担心抗生素和其他抗菌药物可能会促进抗生素抗性基因的水平转移。对于大多数类型的抗菌剂，它们诱导缀合在最小抑制浓度（MIC）以下的能力仍然是未知的。因此，我们的目标是探索常用抗生素和抗菌杀菌剂诱导抗生素抗性水平转移的潜力。使用先前优化的具有复杂细菌群落的基于培养物的测定法，研究了抗生素头孢噻肟，环丙沙星，庆大霉素，红霉素，磺胺甲恶唑，甲氧苄氨嘧啶和抗菌杀生物剂氯己定二葡糖酸盐，十六烷基三甲基氯化铵和三氯生的各种亚MIC浓度的作用作为受体的移动抗性元件供体和可追踪的大肠杆菌菌株。氯己定（24.4μg/ L），三氯生（0.1 mg / L），庆大霉素（0.1 mg / L）和磺胺甲恶唑（1 mg / L）显着提高了抗生素耐药性转移的频率，而对于其他任何测试抗微生物化合物。这相当于氯己定接受者MIC低200倍，三氯生MIC 1/20，磺胺甲恶唑MIC的1/16，庆大霉素MIC低于MIC。据我们所知，这是第一项研究显示三氯生和氯己定可以刺激抗生素耐药性的水平转移。结合最近的研究显示四环素是一种有效的结合诱导剂，我们的结果表明，包括常见抗生素和低浓度抗菌杀生物剂的几种抗菌剂可以通过促进细菌间抗生素耐药性的传播来促进抗生素耐药性的发展。

There is a rising concern that antibiotics, and possibly other antimicrobial agents, can promote horizontal transfer of antibiotic resistance genes. For most types of antimicrobials their ability to induce conjugation below minimal inhibitory concentrations (MICs) is still unknown. Our aim was therefore to explore the potential of commonly used antibiotics and antibacterial biocides to induce horizontal transfer of antibiotic resistance. Effects of a wide range of sub-MIC concentrations of the antibiotics cefotaxime, ciprofloxacin, gentamicin, erythromycin, sulfamethoxazole, trimethoprim and the antibacterial biocides chlorhexidine digluconate, hexadecyltrimethylammoniumchloride and triclosan were investigated using a previously optimized culture-based assay with a complex bacterial community as a donor of mobile resistance elements and a traceableEscherichia coli strain as a recipient. Chlorhexidine (24.4 μg/L), triclosan (0.1 mg/L), gentamicin (0.1 mg/L) and sulfamethoxazole (1 mg/L) significantly increased the frequencies of transfer of antibiotic resistance whereas similar effects were not observed for any other tested antimicrobial compounds. This corresponds to 200 times below the MIC of the recipient for chlorhexidine, 1/20 of the MIC for triclosan, 1/16 of the MIC for sulfamethoxazole and right below the MIC for gentamicin. To our best knowledge, this is the first study showing that triclosan and chlorhexidine could stimulate the horizontal transfer of antibiotic resistance. Together with recent research showing that tetracycline is a potent inducer of conjugation, our results indicate that several antimicrobials including both common antibiotics and antibacterial biocides at low concentrations could contribute to antibiotic resistance development by facilitating the spread of antibiotic resistance between bacteria.

https://www.sciencedirect.com/science/article/pii/S0048969717330309