Azo dyes are the most widely applied chemical dyes that have also raised great concerns for environmental contamination and human health issues. There has been a growing interest in discovering bioremediation methods to degrade azo dyes for environmental and economic purposes. Azoreductases are key enzymes evolved in nature capable of degrading azo dyes. The current work reports the identification, expression, and properties of a novel azoreductase (AzoRed2) from Streptomyces sp. S27 which shows an excellent stability against pH change and organic solvents. To overcome the requirements of coenzyme while degrading azo dyes, we introduced a coenzyme regeneration enzyme, Bacillus subtilis glucose 1-dehydrogenase (BsGDH), to construct a recycling system in living cells. The whole-cell biocatalyst containing AzoRed2 and BsGDH was used to degrade a representative azo dye methyl red. The degradation rate of methyl red was up to 99% in 120 min with high substrate concentration (250 μM) and no external coenzyme added. The degradation rate was still 98% in the third batch trial. To sum up, a novel azoreductase with good properties was found, which was applied to construct whole-cell biocatalyst. Both the enzymes and whole-cell biocatalysts are good candidates for the industrial wastewater treatment and environmental restoration.
|Original language||English (US)|
|Number of pages||10|
|Journal||International Journal of Biological Macromolecules|
|State||Published - Nov 1 2019|
Bibliographical noteFunding Information:
This work was supported by the National Natural Science Foundation of China ( 21636003 and 21672065 ). We thank LetPub ( www.letpub.com ) for its linguistic assistance during the preparation of this manuscript.
- Coenzyme regeneration
- Whole-cell biocatalyst