Methods for increasing nitrile biotransformation into amides using Mesorhizobium sp.
1Department of Environmental Engineering, National Chung Hsing University, Taiwan, ROC. pine.feng@msa.hinet.net
Prikladnaia Biokhimiia I Mikrobiologiia
|July 31, 2008
Summary
Researchers enhanced nitrile hydratase (NHase) activity using specific chemicals. Propionaldehyde significantly boosted acrylonitrile conversion to acrylamide, achieving near 100% conversion efficiently.
Area of Science:
- Biotechnology
- Environmental Science
- Industrial Microbiology
Background:
- Nitriles pose environmental risks as soil pollutants from industrial wastewater.
- Efficient nitrile degradation is crucial for environmental remediation.
- Nitrile hydratase (NHase) is vital for acrylamide production and treating organocyanide contamination.
Purpose of the Study:
- To investigate factors enhancing NHase activity for improved acrylonitrile biotransformation.
- To optimize conditions for efficient conversion of acrylonitrile to acrylamide using Mesorhizobium sp. NHase.
Main Methods:
- Studied whole bacterial cells of Mesorhizobium sp. NHase.
- Assessed the impact of various chemical additives on acrylonitrile conversion rates.
- Identified NHase cofactors and activators/inhibitors.
Main Results:
- Cobalt ions were confirmed as essential NHase cofactors, increasing enzyme activity.
- Propionaldehyde and butyraldehyde enhanced acrylonitrile conversion; propionaldehyde was most effective.
- Near 100% acrylonitrile conversion to acrylamide was achieved in 3.8 hours with optimal propionaldehyde concentration (207.4 mg/l).
- Benzaldehyde showed no positive effect, while EDTA and acrylamide had no impact.
- Silver sulfate (Ag2SO4) exhibited inhibitory effects, with complete inhibition at concentrations above 0.5 mg/l.
Conclusions:
- Mesorhizobium sp. NHase activity can be significantly enhanced by specific chemical additives, particularly propionaldehyde.
- Optimized conditions allow for highly efficient and rapid biotransformation of acrylonitrile to acrylamide.
- Understanding cofactor and activator roles is key to developing effective nitrile degradation strategies.
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