Pruden 0547342 This research opens a new paradigm of viewing biomolecules, such as ARG, prions, ricin, anthrax, etc., as "pollutants". Biomolecules such as these are of increasing health and security concern to society and this program will help to open new approaches to mitigation and treatment. Investigating ARG directly as pollutants using genome-enabled tools, rather than culture-based methods, is an innovative aspect of this research. For the past two years the PI has been studying the spread of ARG in the front range Colorado watershed, which provides an excellent model system for studying the impacts of pharmaceuticals in the environment because the primary source is snowmelt with minimal anthropogenic input. Thus the PI is uniquely poised to succeed in this research and to make significant contributions to the field. Institutional support is substantial, including newly renovated labs, reduced teaching loads, TA support, travel funding, and mentoring.
The intellectual merit of this project will provide a firm foundation for teaching, training and learning. New courses that integrate MB&B into the engineering curriculum will be further developed, evaluated, and improved. Inquiry-based learning and peer-learning with a laboratory component will be especially valuable for training engineers in an interdisciplinary field. MERGE activities will also specifically address the need for representation of women and minorities by focusing on topics that have been demonstrated to attract underrepresented groups. Graduate students will also benefit from MERGE by actively participating as mentors to undergraduate students and in taking the lead in publishing and presenting the results of their research. Furthermore, students will help organize K-12 STEM (Science, Technology, Engineering and Mathematics) outreach activities. Results will be broadly disseminated through conducting workshops in partnership with other Colorado/Wyoming universities and with European collaborators (University of Barcelona and Institut National de la Recherche Agronomique). Finally, the overall results will be summarized as best management practices (BMPs), which will be a helpful practical guide to farming and water professionals. The activities are considered to be beneficial to society in that they will take an important step in involving environmental engineers in helping solve a critical problem that has been identified by the World Health Organization (WHO) as one of the most pressing health issues of this century.
Antibiotic resistance is one of the most serious human health challenges of our time. The incidence of bacterial infections that do not respond to antibiotic treatments has increased measurably since antibiotics were first introduced over fifty years ago and has continued to increase over the past two decades. The typical strategy for fighting antibiotic resistance is to limit antibiotic use and to use proper dosages and complete treatments. While this is an important strategy, more aggressive approaches may be needed to contain antibiotic resistance and maximize the lifespan of antibiotics that reach the market. This NSF CAREER supported research introduced and examined a new strategy for containing antibiotic resistance: control of antibiotic resistance genes in the water environment. Antibiotic resistance genes are segments of DNA the encode the functions that allow bacteria to fight antibiotics. This research advocates the containment and treatment of this DNA in water systems over and above inactivation of the bacteria because DNA that is not destroyed can still be assimilated by other bacteria and allow resistance to continue to spread. In the first objective of this research we established the concept of antibiotic resistance as contaminants and studied their behavior in a model watershed, the Cache La Pouder River in Colorado. This is an ideal model to study because the river originates in the Rocky Mountains, where minimal human influence on antibiotic resistance is expected, and then flows through zones of urban and agricultural land use. We directly quantified antibiotic resistance genes in the sediment and water and revealed that antibiotic resistance genes were significantly higher in the sections of the river impacted by human activity than they were in the Rocky Mountains. In a follow-up study we developed a new tool for tracking the sources of antibiotic resistance genes in the river by examining the patterns of occurrence of several tetracycline and sulfonamide resistance genes called the molecular signatures approach. We used the new approach to determine where the antibiotic resistance genes in the river had originated from and found that the signatures more closely matched bacteria present in wastewater treatment plants and agricultural lagoons than they did the pristine zone in the Rocky Mountains. In the second objective we examined the potential of on farm manure management practices to contain antibiotic resistance genes and found that containment of runoff is likely to be the most effective means of limiting antibiotic resistance spreading from agricultural operations. This practice is equally as important for organically raised animals, which also produce manure containing antibiotic resistance, although slightly lower than conventionally raised animals. In the third objective we examined the potential of water disinfection to destroy antibiotic resistance genes. It was found that UV treatment kills bacteria, but has little effect on DNA. On the other hand, membrane removal (advanced filtration) appeared to be a promising way to control antibiotic resistance genes present in wastewater treatment plant effluent. We also observed that some anaerobic digestion processes used to treat sludge were more effective than others for reducing the presence of antibiotic resistance genes in the resulting biosolids, which are typically used as fertilizer. In terms of broader impacts, this project also had a vital education and outreach component. Through the Mentoring Engineering Research in Genomics and the Environment (MERGE) program, students with diverse backgrounds were brought together and engaged in peer mentoring. The project drew from fundamental principles of molecular biology, biotechnology, ecology, chemistry, hydrology, environmental engineering and others. This interdisciplinary character attracted students with diverse educational, gender, and ethnic backgrounds to graduate studies in engineering. Five Doctoral, four Masters, and eleven undergraduate students contributed directly to this project, and of these sixteen were female, two were Native American, and one was Hispanic, all of which are underrepresented groups in engineering. To enhance interdisciplinary engineering education and help educate the next generation of engineers in molecular biology and biotechnology, a new course was developed, "Molecular Biology for Engineers". This course became a permanent part of the curriculum at Colorado State University. The graduate and undergraduate students also assisted the principle investigator in preparing and delivering environmental engineering and molecular biology and biotechnology educational activities to local elementary, middle school, and high school students. The principle investigator also engaged the agricultural community by presenting results at community meetings, delivering a webcast on the topic, and assisting in the development of fact sheets and a web site. During this award period, a book entitled Hormones and Pharmaceuticals Used in Concentrated Animal Feeding Operations was also co-edited and a book chapter was written on the topic of antimicrobial resistance in the environment.
