2013 NGWA Summit — The National and International Conference on Groundwater

Engineering Molecular Efflux Pumps for Bioremediation of Groundwater

Tuesday, April 30, 2013: 2:15 p.m.
Regency East 2 (Hyatt Regency San Antonio)
Vikram Kapoor, University of Cincinnati
Ranjani Ravi, University of Cincinnati
David Wendell, Ph.D, University of Cincinnati

The present technology standard for removal of emerging contaminants in groundwater is activated carbon, which is commonly used in water treatment for removing a variety of organic contaminants such as synthetic organic chemicals (SOCs), aromatic compounds and natural organic matter (NOM). While activated carbon can remove a broad range of organic substrates, the cost of this prolific absorbance is specificity. Despite the advantage of high COD removal efficiencies, contaminants such as antibiotics escape capture due to their relatively low abundance compared to other organic matter. Also, heat regeneration of activated carbon is critical for efficient removal and increased useful lifetime of the media, but remains energy intensive. Clearly, there is a need for an effective and selective antibiotic removal material, capable of functioning in organics-rich wastewaters with minimum energy input. Here we demonstrate the selective removal of ampicillin and vancomycin, commonly used human and veterinary antibiotics, and ethidium bromide, a common molecular biology reagent, by engineering a light powered proteovesicle molecular assembly using the multidrug efflux pump protein AcrB. We have provided the requisite pmf by coupling this pump to the light-driven proton pump delta-rhodopsin (dR). This creates a solar powered material capable of pumping and capturing antibiotics from bulk solutions. When comparing the removal effeciency of our system to an equivalent amount of activated carbon using river water and sunlight, our vesicle system removed approximately twice as much antibiotic. In addition to capture, our system also offers the ability to recover antibiotics for reuse.  Altogether, the AcrB-dR technology enables an environmental friendly and cost-effective means for extracting antibiotics from surface waters, while also allowing potential antibiotic recovery and reuse through vesicle solubilization.
  Handout


Vikram Kapoor , University of Cincinnati
Vikram Kapoor is a graduate student in the Environmental Engineering and Science Program at the University of Cincinnati. He received a B.S degree in Biotechnology at the Jaypee Institute of Information Technology in India. His research interests include application of molecular tools for microbial source tracking in watersheds. Currently he is working on a project to design an efficient microbial source tracking and evaluation program for the Duck Creek watershed in Hamilton County, Cincinnati, Ohio. Kapoor is also involved in other projects such as the removal of antibiotics from water using nano-engineered protein vesicles.


Ranjani Ravi , University of Cincinnati
Ranjani Ravi is a graduate student in the Environmental Engineering Department at the University of Cincinnati. She completed her undergraduate studies in Electronics and Communications Engineering from the Amrita School of Engineering in India. Currently, she is working on a project involving novel methods to detect norovirus in surface water and groundwater.


David Wendell, Ph.D , University of Cincinnati
David Wendell is an Assistant Professor at the University of Cincinnati in the School of Energy, Environmental, Biological and Medical Engineering. Dr. Wendell received his BS and MS from Cornell University in Biological and Environmental Engineering and his PHD in Biomedical Engineering from UCLA. His current work spans several different areas of nanobiological science including protein based nanopores; repurposed microbial multidrug efflux pumps for bioremediation; grey water risk assessment using human mitochondrial DNA and most notably, artificial photosynthesis, research which recently garnered him the 2010 International Earth Award.