TY - JOUR
T1 - Changes in microbiological metabolism under chemical stress
AU - Ray, Sujata
AU - Peters, Catherine Anne
N1 - Funding Information:
This work was funded by a grant from the National Science Foundation, project number BES-0302432. We are grateful to Dr. Nancy G. Love for providing the bacterial culture and to Dr. Robert M. Cowan for his invaluable contributions in respirometric methods.
PY - 2008/3
Y1 - 2008/3
N2 - 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 on microbiological metabolism 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. Stressor DNP, between 49 and 140 mg l-1, and PCP, at 15 and 38 mg l-1, caused decreases in biomass growth yields, but did not inhibit substrate utilization rates. These effects increased with stressor concentrations, showing as much as a 10% yield reduction at the highest DNP concentration. This suggests that a portion of carbon and energy resources are diverted from growth and used in stress management and protection. Stressor DNP, between 300 and 700 mg l-1, and PCP at 85 mg l-1 caused decreases in growth yields and substrate utilization rates. This suggests an inhibition of both anabolism and catabolism. Stressor NEM was the most potent, inhibiting biological activity at concentrations as low as 2.7 mg l-1. These findings will ultimately be useful in better monitoring and management of biological treatment operations and contaminated natural systems.
AB - 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 on microbiological metabolism 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. Stressor DNP, between 49 and 140 mg l-1, and PCP, at 15 and 38 mg l-1, caused decreases in biomass growth yields, but did not inhibit substrate utilization rates. These effects increased with stressor concentrations, showing as much as a 10% yield reduction at the highest DNP concentration. This suggests that a portion of carbon and energy resources are diverted from growth and used in stress management and protection. Stressor DNP, between 300 and 700 mg l-1, and PCP at 85 mg l-1 caused decreases in growth yields and substrate utilization rates. This suggests an inhibition of both anabolism and catabolism. Stressor NEM was the most potent, inhibiting biological activity at concentrations as low as 2.7 mg l-1. These findings will ultimately be useful in better monitoring and management of biological treatment operations and contaminated natural systems.
KW - Dinitrophenol
KW - Growth yield
KW - N-ethylmaleimide
KW - Pentachlorophenol
KW - Pseudomonas aeruginosa
KW - Respirometry
UR - http://www.scopus.com/inward/record.url?scp=43049114138&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=43049114138&partnerID=8YFLogxK
U2 - 10.1016/j.chemosphere.2007.10.026
DO - 10.1016/j.chemosphere.2007.10.026
M3 - Article
C2 - 18262219
AN - SCOPUS:43049114138
SN - 0045-6535
VL - 71
SP - 474
EP - 483
JO - Chemosphere
JF - Chemosphere
IS - 3
ER -