ENVIRONMENTAL RESERVOIRS OF ANTIBIOTIC RESISTANCE

该子项目是利用该技术的众多研究子项目之一 资源由 NIH/NCRR 资助的中心拨款提供。子项目和 研究者 (PI) 可能已从 NIH 的另一个来源获得主要资金， 因此可以在其他 CRISP 条目中表示。列出的机构是 对于中心来说，它不一定是研究者的机构。 抗生素耐药性是世界上最紧迫的公共卫生问题之一。为了人类和动物健康而广泛使用抗生素导致废水和淡水生态系统中抗生素的含量增加。研究表明，水中抗生素含量的增加会导致抗生素耐药性的发生率增加。我们假设废水处理厂（WWTP）废水是环境中抗生素和抗生素抗性细菌的来源，并有助于建立抗生素抗性环境库。因此，我们建议对接收污水处理厂废水的淡水生态系统中的细菌进行表征。将研究大肠菌群，因为它们是淡水生态系统中的常见污染物，是一组经过充分研究的生物体，并且某些菌株会导致人类疾病。气单胞菌也将被研究，因为它们在淡水生态系统中无处不在，并且一些菌株也是人类病原体。将研究细菌对三种不同类别抗生素（β-内酰胺类、四环素类、氟喹诺酮类）中的三种抗生素的耐药性。将检查抗生素耐药性的发生率、抗生素耐药性水平以及抗生素耐药性的遗传决定因素。样品将在 Tahlequah Creek 沿岸的三个地点采集（一处位于污水处理厂上游，一处位于污水处理厂下游，污水来自污水处理厂）。将使用 EPA 批准的最可能数 (MPN) 方法对水样中的总大肠菌群和大肠杆菌水平进行计数。将使用相同的方法通过向水样中添加抗生素来计数抗生素耐药细菌。使用 MPN 试剂盒和差异培养基从废水和沉积物样品中分离抗生素耐药细菌。将根据分离株的 16S rDNA 序列进行鉴定，然后测试其对各种抗生素的耐药性。耐药性的分子基础将使用已发表的方法（PCR、IEF）确定。将定期收集数据和分离株，并用于评估该生态系统中抗生素抗性和抗性基因的稳定性和持久性。未来的计划包括检查细菌物种内部和之间抗生素抗性基因的水平基因转移以及基因转移所涉及的机制。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Antibiotic resistance is one of the world's most pressing public health problems. Widespread use of antibiotics for human and animal health has led to increased levels of antibiotics in wastewater and freshwater ecosystems. Studies indicate that increased levels of antibiotics in water contribute to an increased incidence of antibiotic resistance. It is our hypothesis that wastewater treatment plant (WWTP) effluent is a source of antibiotics and antibiotic resistant bacteria in the environment and contributes to the establishment of environmental reservoirs of antibiotic resistance. Therefore, we propose to characterize bacteria in a freshwater ecosystem that receives effluent from a WWTP. Coliforms will be studied as they are common pollutants in freshwater ecosystems, a well-studied group of organisms, and some strains cause disease in humans. Aeromonads will also be studied as they are ubiquitous in freshwater ecosystems and some strains are human pathogens also. Resistance of bacteria to three antibiotics from three different classes of antibiotics (beta-lactams, tetracyclines, fluoroquinolones) will be studied. Incidence of antibiotic resistance, levels of antibiotic resistance, and genetic determinants of antibiotic resistance will be examined. Samples will be taken at three sites along Tahlequah Creek (one upstream and one downstream of the WWTP and effluent from the WWTP). Enumeration of total coliforms and E. coli levels in water samples will be performed using an EPA-approved most probable number (MPN) method. Enumeration of antibiotic resistant bacteria will be performed using the same method by adding antibiotics to the water samples. Antibiotic resistant bacteria will be isolated from effluent and sediment samples using the MPN kits and differential media. Isolates will be identified based on their 16S rDNA sequences then tested for resistance to various antibiotics. The molecular basis for resistance will be determined using published methods (PCR, IEF). Data and isolates will be collected at regular intervals and used to assess the stability and persistence of antibiotic resistance and resistance genes in this ecosystem. Future plans include examination of horizontal gene transfer of antibiotic resistance genes within and between bacterial species and the mechanisms involved in gene transfer.