ENVIRONMENTAL RESERVOIRS OF ANTIBIOTIC RESISTANCE

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 抗生素耐药性是世界上最紧迫的公共卫生问题之一。为了人类和动物的健康，抗生素的广泛使用导致废水和淡水生态系统中抗生素水平的增加。研究表明，水中抗生素水平的增加会增加抗生素耐药性的发生率。我们的假设是，污水处理厂(WWTP)出水是环境中抗生素和抗生素耐药细菌的来源，并有助于环境中抗生素耐药性水库的建立。因此，我们建议对接受污水处理厂出水的淡水生态系统中的细菌进行表征。将对大肠菌群进行研究，因为它们是淡水生态系统中的常见污染物，这是一组研究得很好的生物体，而且一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，一些菌株也是人类的病原体。将研究细菌对来自三种不同类别抗生素(β-内酰胺类、四环素类、氟喹诺酮类)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。样本将在大莱溪沿岸的三个地点(一个在污水处理厂的上游和一个下游，以及污水处理厂的流出物)采集。水样本中的总大肠菌群和大肠杆菌水平将使用美国环保局批准的最可能数字(MPN)方法进行计数。对抗药性细菌的点算将采用相同的方法，即在水样中加入抗生素。将使用MPN试剂盒和差异培养基从废水和沉积物样本中分离出抗药性细菌。分离株将根据其16S rDNA序列进行鉴定，然后进行对各种抗生素的抗药性测试。抗性的分子基础将使用已公布的方法(PCR，IEF)来确定。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耐药性和耐药性基因的稳定性和持久性。未来的计划包括检查抗生素耐药性基因在细菌物种内和细菌之间的水平基因转移，以及基因转移涉及的机制。

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.