The Growth Yield of Aminobacter niigataensis MSH1 on the Micropollutant 2,6-Dichlorobenzamide Decreases Substantially at Trace Substrate Concentrations
- Author(s)
- Bart Raes, Jinsong Wang, Benjamin Horemans, Lode Dirckx, Steffen Waldherr, Hans Peter E. Kohler, Dirk Springael
- Abstract
2,6-Dichlorobenzamide (BAM) is an omnipresent micropollutant in European groundwaters. Aminobacter niigataensis MSH1 is a prime candidate for biologically treating BAM-contaminated groundwater since this organism is capable of utilizing BAM as a carbon and energy source. However, detailed information on the BAM degradation kinetics by MSH1 at trace concentrations is lacking, while this knowledge is required for predicting and optimizing the degradation process. Contaminating assimilable organic carbon (AOC) in media makes the biodegradation experiment a mixed-substrate assay and hampers exploration of pollutant degradation at trace concentrations. In this study, we examined how the BAM concentration affects MSH1 growth and BAM substrate utilization kinetics in a AOC-restricted background to avoid mixed-substrate conditions. Conventional Monod kinetic models were unable to predict kinetic parameters at low concentrations from kinetics determined at high concentrations. Growth yields on BAM were concentration-dependent and decreased substantially at trace concentrations; i.e., growth of MSH1 diminished until undetectable levels at BAM concentrations below 217 μg-C/L. Nevertheless, BAM degradation continued. Decreasing growth yields at lower BAM concentrations might relate to physiological adaptations to low substrate availability or decreased expression of downstream steps of the BAM catabolic pathway beyond 2,6-dichlorobenzoic acid (2,6-DCBA) that ultimately leads to Krebs cycle intermediates for growth and energy conservation.
- Organisation(s)
- Functional and Evolutionary Ecology
- External organisation(s)
- Katholieke Universiteit Leuven, Eidgenössische Anstalt für Wasserversorgung, Abwasserreinigung und Gewässerschutz
- Journal
- Environmental Science and Technology
- Volume
- 58
- Pages
- 2859-2869
- No. of pages
- 11
- ISSN
- 0013-936X
- DOI
- https://doi.org/10.1021/acs.est.3c06883
- Publication date
- 02-2024
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 106022 Microbiology, 208003 Environmental biotechnology, 106044 Systems biology
- Keywords
- ASJC Scopus subject areas
- Chemistry(all), Environmental Chemistry
- Sustainable Development Goals
- SDG 7 - Affordable and Clean Energy
- Portal url
- https://ucris.univie.ac.at/portal/en/publications/the-growth-yield-of-aminobacter-niigataensis-msh1-on-the-micropollutant-26dichlorobenzamide-decreases-substantially-at-trace-substrate-concentrations(c6f4f7a3-f772-45ab-b7f2-f70f7451db3c).html