Biodegradation of profenofos, an acetylcholine esterase inhibitor by a psychrotolerant strain Rahnella sp. PFF2 and degradation pathway analysis

Profenofos (PFF) is an organophosphate insecticide and used worldwide to control harmful pests and insect populations. Removal of PFF from the environment is important because of its high mammalian acute toxicity due to acetylcholinesterase enzyme inhibition. Biodegradation in this context is beneficial as it is a cost-effective and sustainable process. In the present study, microbial degradation of PFF was investigated by using a psychrotolerant bacterium Rahnella sp. PFF2. The bacterial strain was isolated from the soil samples of apple orchards situated in Kufri, Himachal Pradesh, India. Quantitative analysis through High-performance liquid chromatography revealed that the bacterium PFF2 was able to degrade 100% PFF (50 mu g/ml) within 14 days at 20 degrees C, within 16 days at 28 degrees C, and within 20 days at 15 degrees C. GC/MS and HPLC studies showed the presence of pathway metabolites 4-Bromo-2-chlorophenol, phosphoric acid, and 3, 4 - dimethyl benzoic acid. Based on these data a probable PFF degradation pathway has been proposed. An inducible and intracellular organophosphorus hydrolase enzyme might responsible for the initial degradation process. To the best of our knowledge, the current finding is the first report of PFF degradation at both the psychrophilic and mesophilic temperature conditions by any psychrotolerant Rahnella sp. isolated from Western Himalayan regions.

Automated summary

The study investigated microbial degradation of Profenofos (PFF) using a psychrotolerant bacterium Rahnella sp. PFF2, isolated from soil samples in India. Results showed that the bacterium could effectively degrade PFF at different temperatures, with GC/MS and HPLC studies revealing degradation pathway and metabolites, proposing a possible degradation mechanism. This is the first report of PFF degradation by a psychrotolerant Rahnella sp. at both psychrophilic and mesophilic temperature conditions in the Western Himalayan regions.