A DIFFUSION GRADIENT SYSTEM FOR ISOLATING MICROORGANISMS AND STUDYING MICROBIAL PROCESSES RELATED TO DETOXIFICATION OF HAZARDOUS CHEMICALS

MICROORGANISMS ARE PRIMARILY RESPONSIBLE FOR THE DEGRADATION OF TOXIC CHEMICALS THAT ENTER THE ENVIRONMENT. SUCCESSFUL ISOLATION AND EXPLOITATION OF THESE MICROBES FOR BIOREMEDIATION REQUIRES IDENTIFYING THE PHYSICO-CHEMICAL CONDITIONS UNDER WHICH DETOXICATION ACTIVITY IS MAXIMIZED. THIS WORK IS DEVELOPING AN ANALYTICAL DIFFUSION GRADIENT CHAMBER THAT MIMICS THE DIFFUSIVE PROCESSES THAT PREVAIL IN THE MICROBIAL WORLD. THIS SYSTEM CAN BE USED TO SEPARATE, ENRICH, AND ISOLATE DETOXIFYING MICROORGANISMS, AS WELL AS STUDY THE BEHAVIOR OF, AND DETOXIFICATION PROCESSES MEDIATED BY, THESE ORGANISMS. THE SYSTEM CONSISTS OF A GRADIENT CHAMBER FOR CULTURING MICROORGANISMS IN MULTIPLE, CONTINUOUS DIFFUSION GRADIENTS OF SMALL SOLUBLE MOLECULES. IN ADDITION, THERE IS AN EFFLUENT CHAMBER FOR CONSOLIDATING EFFLUENT FLOW FROM THE SYSTEM, AN ENVIRONMENTAL CONTROL UNIT FOR MAINTAINING CONSTANT TEMPERATURE, AND AN IMAGING UNIT TO MONITOR AND QUANTIFY MICROBIAL GROWTH AND MOVEMENT. SCIENTISTS USE THE SYSTEM TO EVALUATE THE CHEMOTACTIC RESPONSE OF AN INDIVIDUAL BACTERIAL SPECIES TO MULTIPLE CHEMICAL CUES. IN ADDITION, GRADIENTS OF SALT AND TOLUENE ARE USED TO EVALUATE THE RESPONSE OF A NATURAL COMMUNITY FROM A SOIL SITE CONTAMINATED WITH OIL BRINE. MATHEMATICAL MODELS ARE ALSO BEING DEVELOPED THAT AID IN OPTIMIZING THE PEFORMANCE OF THE SYSTEM.