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Cyanide Biodegradation by Trichoderma harzianum and Cyanide Hydratase Network Analysis
Narges Malmir1,2, Mohammadreza Zamani1,2, Mostafa Motallebi1,2
1National Institute of Genetic Engineering and Biotechnology (NIGEB), Shahrak-e Pajoohesh km 15, Tehran-Karaj Highway, Tehran P.O. Box 14965/161, Iran.
Molecules (Basel, Switzerland)
|May 28, 2022
Summary
Trichoderma harzianum efficiently degrades cyanide, a toxic chemical. This fungus shows significant potential for bioremediation, with molecular analysis confirming its detoxification capabilities.
Area of Science:
- Environmental microbiology
- Biotechnology
- Bioremediation
Background:
- Cyanide is a highly toxic chemical that inhibits essential metalloenzymes like cytochrome C oxidase.
- Cyanide biodegradation involves various pathways and enzymes, including cyanide hydratase.
- Effective bioremediation strategies are crucial for mitigating cyanide pollution.
Purpose of the Study:
- To identify fungal strains with high cyanide resistance and degradation capabilities for bioremediation.
- To assess the efficiency of selected strains in cyanide detoxification.
- To confirm the genetic basis of cyanide detoxification in promising strains.
Main Methods:
- Screening of 24 fungal strains for cyanide resistance and degradation.
- Assessing bioremediation efficiency at a 15 mM cyanide concentration.
- Molecular analysis to identify genes involved in cyanide detoxification pathways.
Main Results:
- Trichoderma harzianum demonstrated significant cyanide resistance and degradation, achieving 75% efficiency in 7 days at 15 mM cyanide.
- Gene network analysis identified key enzymes including cyanide hydratase, dipeptidase, carbon-nitrogen hydrolase-like protein, and ATP adenylyltransferase.
- T. harzianum exhibited superior cyanide degradation compared to other tested fungal strains.
Conclusions:
- Trichoderma harzianum is a highly effective organism for cyanide bioremediation.
- The study validates the role of specific enzymes and genes in fungal cyanide detoxification.
- Findings support the application of T. harzianum in environmental cleanup of cyanide-contaminated sites.
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