"Bioremediation & Biomonitoring
Issues Addressed in OK EPA EPSCoR Program"
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Water, water everywhere and not a drop to drink!" is a situation that several Oklahoma research groups are working to prevent through bioremediation and biomonitoring. Shortly after the Center for Sensors and Sensor Technologies was established in 1997, a team of scientists brought together by the Center was successful in securing a $300,000+ Environmental Protection Agency EPSCoR grant to develop a new type of sensor for detecting groundwater pollutants. Dr. Jack Bantle, then OSU Arts and Sciences Associate Dean for Research, was pro- ject director. When Dr. Bantle left OSU last year, Dr. Robert Miller, a professor in the Department of Microbiology and Molecular Genetics, stepped in as director. According to Miller, the program centers on the improvement of science and technology in Oklahoma, the development of human resources, and the improvement of specialized research facilities in the state. The project, a collaborative effort involving OSU, the University of Oklahoma, the University of Tulsa, and the OU Health Sciences Center, focuses on three major areas. One is the Detection, Isolation, and Characterization of Microorganisms Responsible for the Anaerobic Biodegradation of Gas Condensate Hydrocarbons. This research team is headed by Dr. Joe Suflita, OU Department of Botany and Microbiology, and he is joined by Dr. Kerry Sublette, University of Tulsa, and Dr. Ralph Tanner and Dr. M.J. McInnerny, also from OU. They are investigating the mechanisms of the intrinsic bioremediation of petroleum hydrocarbons in the subsurface at an active natural gas production site in Colorado, operated by Amoco Production Company, where soil and groundwater have been contaminated with gas condensate. Because of the sizeable petroleum industry in Oklahoma and the region, a nonintervention type of remediation could save thousands of dollars and allow nature to remove the contaminants without human interference. The second area deals with Environmental and Molecular Toxicology and Zinc Finger Proteins. This research focuses on the interactions of xenobiotics, or foreign chemical compounds and pollutants, with zinc finger proteins and on the potential health effects of such interactions. Alterations in the way genetic material is replicated and expressed can lead to many human diseases including cancer, reproductive and birth defects and organ dysfunction. This study is using the zinc finger protein assay for biomonitoring toxic agents in groundwater samples at the Norman, Oklahoma landfill. Dr. Jay Hanas, OU Health Sciences Center, is the primary investigator for this research. The third segment of the grant deals with the Development of Cytochrome p45-Based Sensors for Monitoring Organism Xenobiotics in Groundwater. Sources of hazardous wastes are numerous and scattered worldwide. This research is aimed at designing sensors that are capable of simultaneously detecting a large variety of xenobiotics. These sensors could be strategically located to provide a relatively inexpensive way of triggering automated systems to interpret the data that are gathered. To date, there is concrete evidence that the system can detect the presence of the following xenobiotcs in groundwater: hexacloroethane (0.5 mg/mL), carbon tetrachloride (20 mg/mL), biphenyl (5 mg/mL), and others. Additional toxic xenobiotics are under investigation. Again the Norman landfill site is the testing ground for these sensors. The knowledge gained from these studies can be applied to other sites throughout the nation. Dr. Mario Rivera, OSU Department of Chemistry, is the principal investigator of this segment. Dr. Gilbert John, OSU Department of Microbiology and Molecular Genetics, and Dr. Gary Yen, OSU Department of Electrical/Computer Engineering, are members of this research group. The researchers credit the CSST with helping bring them together from their various disciplines and helping support them in their efforts to obtain funding for their project. In addition to serving as director for the EPA EPSCoR program, Dr. Miller conducts sensor-related research involving bacterial responses to ultraviolet (UV) light. Exposure to natural and artificial ultraviolet light can be both mutagenic and lethal. During the Antarctic spring, ozone thinning significantly increases the intensity of the ultraviolet light reaching the surface of the continent. Even though the Antarctic seems far away and perhaps unimportant to crop production and human cancer rates, this ozone hole is of concern because environmental bacteria, particularly marine bacteria, play important roles in the planetary food web, in producing oxygen, and in cycling other elements. Perhaps the most important regulator of bacterial response in UV exposure is the recA gene's protein product, RecA. Miller's group has attempted to develop a biosensor for monitoring RecA activity in environmental bacteria, entailing the development of a noninvasive, nondestructive, but sensitive means for measuring this activity. Two of the lux operon used contain genes encoding several proteins, luxA and luxB, which encode luciferase. Luciferase is an enzyme that produces bioluminescent light. Others, luxC, luxD, and luxE, encode proteins that produce the chemical substrate used in the reaction. When the recA promoter is activated by exposure to DNA-damaging stress in cells containing this construct, more luciferase is produced and hence, more light is emitted. The time required to produce light, the maximal level of light produced, and the duration are directly proportional to the level of exposure to UV or comparable stress. Thus, this biosensor should be very useful in assessing the level of exposure of bacterial populations to DNA-damaging stresses in situ. In addition, Miller has used this construction to study the response of microbial biofilm communities to LTV radiation. These studies demonstrate the potential of this biosensor in environmental studies.The CSST recently provided support for one of Dr. Miller's students to present a paper related to this research at the BIOSENSORS 2000 conference in San Diego. For more information, contact Dr. Miller at rum67@okstate.edu or visit his website at http://microbiology.okstate.edu/faculty/rum67/index.html. |
