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Research progress of PAHs degrading genes and enzymes

Polycyclic aromatic hydrocarbons (PAHs) in the environment are highly genotoxic and carcinogenic, teratogenic and mutagenic, and their biodegradation genes and enzymes have attracted much attention. PAHs dioxygenase is one of the key enzymes for PAHs degradation, which is mainly produced by bacteria. It can open the rings of PAHs to form small molecule intermediate products through oxidation reaction, and finally oxidize to CO2 and water. At present, researches on the physicochemical properties, structural characteristics and functions of these enzymes have been carried out one after another. In this paper, the research status and development trend of PAHs degradation genes and enzymes were reviewed.