Deltamethrin transformation by Bacillus thuringiensis and the associated metabolic pathways.

The biological toxicity of deltamethrin at molecular level has been investigated, whereas, the proteome responsive mechanisms of cells under deltamethrin stress at the phylogenetic level are not clear. The proteome expression, transformation-related pathway and regulatory network of Bacillus thuringiensis during the process of deltamethrin transformation were explored using proteomics and metabolomics approaches in the present study. The results showed that deltamethrin was effectively removed by B. thuringiensis within 48 h. The stress responses of B. thuringiensis were activated to resist deltamethrin stress, with significant differential expression of proteins that were primarily involved in the synthesis of DNA and shock proteins, endospore formation, carbon metabolism. The expression patterns of ribosomal proteins confirmed that the transcription and translation of DNA, and biosynthesis of heat shock proteins were inhibited as deltamethrin transformation. The synthesis of oxaloacetate and acetyl-CoA were also hindered, resulting in downregulated expression of carbohydrate metabolism, TCA cycle and energy metabolism. Meanwhile, endospore formation and germination were promoted to resist oxidative stress induced by deltamethrin. These findings imparted novel insight to elucidate underlying stress response mechanisms of the organism under target contaminants stress, and the interaction between deltamethrin transformation and cellular metabolism at the pathway and network levels.