College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310029 China.
The Ohio State University, The Ohio Agricultural Research and Development Center (OSU/OARDC), Wooster, OH 44691, United States.
Sci Total Environ. 2014 Sep 15;493:445-53. doi: 10.1016/j.scitotenv.2014.05.114. Epub 2014 Jun 21.
There is growing evidence that bacteria, in the natural environment (e.g. the soil), can exhibit naturally occurring resistance/degradation against synthetic antibiotics. Our aim was to assess whether soils, not previously exposed to synthetic antibiotics, contained bacterial strains that were not only antibiotic resistant, but could actually utilize the antibiotics for energy and nutrients. We isolated 19 bacteria from four diverse soils that had the capability of growing on penicillin and neomycin as sole carbon sources up to concentrations of 1000 mg L(-1). The 19 bacterial isolates represent a diverse set of species in the phyla Proteobacteria (84%) and Bacteroidetes (16%). Nine antibiotic resistant genes were detected in the four soils but some of these genes (i.e. tetM, ermB, and sulI) were not detected in the soil isolates indicating the presence of unculturable antibiotic resistant bacteria. Most isolates that could subsist on penicillin or neomycin as sole carbon sources were also resistant to the presence of these two antibiotics and six other antibiotics at concentrations of either 20 or 1000 mg L(-1). The potentially large and diverse pool of antibiotic resistant and degradation genes implies ecological and health impacts yet to be explored and fully understood.
越来越多的证据表明,细菌在自然环境(例如土壤)中可以表现出对合成抗生素的天然抗性/降解。我们的目的是评估以前未接触过合成抗生素的土壤是否含有不仅具有抗药性,而且实际上可以将抗生素用作能源和营养物质的细菌菌株。我们从四个不同的土壤中分离出了 19 株细菌,这些细菌能够在青霉素和新霉素的浓度高达 1000mg/L 时作为唯一的碳源生长。这 19 株细菌分离株代表了变形菌门(84%)和拟杆菌门(16%)中多样化的物种。在四种土壤中检测到了 9 种抗生素抗性基因,但其中一些基因(即 tetM、ermB 和 sulI)在土壤分离株中未被检测到,表明存在不可培养的抗生素抗性细菌。大多数能够以青霉素或新霉素作为唯一碳源生存的分离株对这两种抗生素以及另外六种抗生素的浓度为 20 或 1000mg/L 时也具有抗性。大量且多样化的抗生素抗性和降解基因库意味着尚未探索和充分理解其对生态和健康的影响。