Biological Degradation of Nerve Agents

This is the authors' abstract. We don't add key points for this paper.

Objective: The aim of the present study was to determine biodegradation efficacy of nerve agents [methyl parathion, dimethyl methylphosphonate (DMMP), and sarin (GB)] by bacteria isolated from and characterization of isolates. Methods: Enrichment for bacteria that can use organophosphates (OPs) as a source of carbon from the soil, where the synthesis of organophosphorus (OP) compounds takes place. The enrichment of bacteria biodegrading OP compounds was carried out inmineral salt medium. Characterization of bacterial strains was done by sequencing, pyro GC, SDS-PAGE profiling and 16S rRNA. Degradation of OP compounds by bacterial isolates was determined by estimating inorganic phosphorus, gas chromatography and mass spectrometry analyses (GC/MS). Results: After enrichment the bacteria were isolated. OPs were utilized as second preferred carbon source after glucose by these bacteria, whereas acetate and lactose exhibitedminimal effect on growth. These isolates were grouped together based on pyro GC and PAGE profiles and identified by 16S rRNA sequencing. Degradation of OP compounds was determined by the estimation of inorganic phosphorus after 12 and 24h of incubation. GC analysis revealed spp. of Pseudomonas and Acinetobactor effectively degraded the 200ppm concentration of OP compound up to 48.3%, and 59.8% respectively; after 24h of incubation. Conclusion: Organophosphate compounds are extensively used as agricultural pesticides and some are listed chemical warfare agents by Organization for Prohibition of Chemical Weapons (OPCW); these compounds are highly toxic, show environmental persistence and contribute to numerous cases of poisoning. Therefore, the ability of microorganisms to reduce contaminants has been a preferred method to degrade these compounds. The biodegradation of methyl parathion, dimethyl methylphosphonate (DMMP), and GB proceeded rapidly with the formation of a series of intermediate products, which were analyzed using a combination GC/MS.