Microbiological responses and adaptation to chemical stress

ENVR 108

Sujata Ray, sray@princeton.edu, Department of Civil Engineering, Princeton University, Princeton, NJ 08544 and Catherine A. Peters, cap@princeton.edu, Department of Civil and Environmental Engineering, Princeton University, Princeton, NJ 08544.
Chemical stress may alter microbiological metabolism and this, in turn, may affect the natural and engineered systems where these organisms function. The impact of chemical stress was investigated using model chemicals 2,4-dinitrophenol (DNP), pentachlorophenol (PCP) and N-ethylmaleimide (NEM). Biological activity of Pseudomonas aeruginosa was measured in batch systems, with and without stressors at sub-lethal concentrations. At specific concentrations, DNP and PCP caused decreases in biomass growth yields, but did not inhibit substrate utilization rates. These effects increased with stressor concentrations. This suggests that a portion of carbon and energy resources are diverted from growth and used in stress management. At higher concentrations, DNP and PCP caused decreases in growth yields and substrate utilization rates. This suggests an inhibition of both anabolism and catabolism. NEM inhibited biological activity at concentrations as low as 2.7 mg/L. Investigation of adaptive responses revealed that pre-exposure weakened the microbial populations at specific stressor concentrations.
 

General Topics
2:00 PM-4:10 PM, Wednesday, August 22, 2007 Boston Park Plaza -- Beacon Hill Rm, Oral

Division of Environmental Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007