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Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase
Published on: December 4, 2017
Kinetics of a hydrogen-oxidizing, perchlorate-reducing bacterium
Robert Nerenberg1, Yasunori Kawagoshi, Bruce E Rittmann
1Department of Civil and Environmental Engineering, Northwestern University, Evanston, Illinois 60208-3109, USA. nerenberg.1@nd.edu
Water Research
|August 30, 2006
Summary
This study details kinetic parameters for Dechloromonas sp. PC1, a hydrogen-oxidizing perchlorate-reducing bacterium (PCRB). It found low perchlorate affinity and observed chlorate accumulation and inhibition, impacting bioremediation strategies.
Area of Science:
- Environmental microbiology
- Bioremediation
- Biogeochemical cycles
Background:
- Perchlorate-reducing bacteria (PCRB) are crucial for perchlorate and chlorate remediation.
- Understanding the kinetics of these microbes is essential for optimizing bioremediation processes.
- Dechloromonas sp. PC1 is a hydrogen-oxidizing PCRB with limited kinetic data.
Purpose of the Study:
- To determine the first kinetic parameters for Dechloromonas sp. PC1.
- To investigate chlorate accumulation and its effect on perchlorate reduction.
- To elucidate the mechanism of chlorate inhibition in PCRB.
Main Methods:
- Batch culture experiments were conducted to measure kinetic parameters.
- Perchlorate and chlorate concentrations were monitored over time.
- Enzyme kinetics were analyzed to understand inhibition mechanisms.
Main Results:
- The maximum specific growth rate (qmax) for perchlorate and chlorate reduction were 3.1 and 6.3 mg/mgDW-day.
- A low Michaelis constant (K) of 0.14 mg/L for perchlorate indicates high affinity.
- Chlorate accumulated and inhibited perchlorate reduction, suggesting competitive inhibition at the (per)chlorate reductase enzyme.
Conclusions:
- Dechloromonas sp. PC1 exhibits efficient perchlorate reduction kinetics.
- Chlorate accumulation and inhibition pose challenges for bioremediation.
- Competitive inhibition by chlorate is a key factor affecting perchlorate reduction rates.
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