Methodology for assessing respiration and cellular incorporation of radiolabeled substrates by soil microbial communities (journal version)
Abstract
A method is described for determining biodegradation kinetics of both naturally occurring and xenobiotic compounds in surface and subsurface soil samples. The method measures both respiration and uptake into cellular biomass of 14C-labeled substrates. After separation of the cells and the soil particles by centrifugation, the cells were trapped on membrane filters for liquid scintillation counting. Mass balances were easily obtained. The technique was used to measure metabolic activity in soil profiles, including unsaturated and saturated zones. First-order rate constants were determined for amino acid metabolism and for m-cresol metabolism. Saturation kinetics were observed for amino acids and m-cresol. m-Cresol values for uptake often exceeded those for respiration by greater than a factor of ten. Saturation was not observed in many horizons. Frequently, respiration obeyed saturation kinetics, whereas uptake was first order. It is concluded that measuring only kinetics of respiration may lead to severe underestimations of biodegradation rates.
- Authors:
- Publication Date:
- Research Org.:
- North Carolina Univ., Chapel Hill (USA). Dept. of Environmental Sciences and Engineering
- OSTI Identifier:
- 6586114
- Report Number(s):
- PB-89103188/XAB
- Resource Type:
- Technical Report
- Resource Relation:
- Other Information: Pub. in Microbial Ecology, Vol. 15, No. 3, 257-273(May 1988)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 54 ENVIRONMENTAL SCIENCES; CARBON 14; TRACER TECHNIQUES; MICROORGANISMS; METABOLISM; NUTRIENTS; BIODEGRADATION; SOILS; XENOBIOTICS; KINETICS; RADIOACTIVITY; RESPIRATION; BETA DECAY RADIOISOTOPES; BETA-MINUS DECAY RADIOISOTOPES; CARBON ISOTOPES; CHEMICAL REACTIONS; DECOMPOSITION; EVEN-EVEN NUCLEI; ISOTOPE APPLICATIONS; ISOTOPES; LIGHT NUCLEI; NUCLEI; RADIOISOTOPES; YEARS LIVING RADIOISOTOPES; 510101* - Environment, Terrestrial- Basic Studies- Radiometric Techniques- (-1989)
Citation Formats
Dobbins, D C, and Pfaender, F K. Methodology for assessing respiration and cellular incorporation of radiolabeled substrates by soil microbial communities (journal version). United States: N. p., 1988.
Web.
Dobbins, D C, & Pfaender, F K. Methodology for assessing respiration and cellular incorporation of radiolabeled substrates by soil microbial communities (journal version). United States.
Dobbins, D C, and Pfaender, F K. 1988.
"Methodology for assessing respiration and cellular incorporation of radiolabeled substrates by soil microbial communities (journal version)". United States.
@article{osti_6586114,
title = {Methodology for assessing respiration and cellular incorporation of radiolabeled substrates by soil microbial communities (journal version)},
author = {Dobbins, D C and Pfaender, F K},
abstractNote = {A method is described for determining biodegradation kinetics of both naturally occurring and xenobiotic compounds in surface and subsurface soil samples. The method measures both respiration and uptake into cellular biomass of 14C-labeled substrates. After separation of the cells and the soil particles by centrifugation, the cells were trapped on membrane filters for liquid scintillation counting. Mass balances were easily obtained. The technique was used to measure metabolic activity in soil profiles, including unsaturated and saturated zones. First-order rate constants were determined for amino acid metabolism and for m-cresol metabolism. Saturation kinetics were observed for amino acids and m-cresol. m-Cresol values for uptake often exceeded those for respiration by greater than a factor of ten. Saturation was not observed in many horizons. Frequently, respiration obeyed saturation kinetics, whereas uptake was first order. It is concluded that measuring only kinetics of respiration may lead to severe underestimations of biodegradation rates.},
doi = {},
url = {https://www.osti.gov/biblio/6586114},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Jan 01 00:00:00 EST 1988},
month = {Fri Jan 01 00:00:00 EST 1988}
}