Biocatalysis and Biotransformation (2020): 1-8.
A native strain of Bacillus endophyticus, PC was found to be effective in demethylation of colchicine. The strain was isolated from rhizospheric soils of Gloriosa superba from Erode, Tamilnadu, and was grown in optimised conditions of carbon and nitrogen. To intensify the demethylation, the strain was enriched and grown for 15 generations starting from low (0.5 mg/ml) to very high (10 mg/ml) concentrations of colchicine. Owing to enrichment, B. endophyticus showed an MIC of 25 mg/ml, and notable activity of demethylation of colchicine. Maximum production was observed at idiophase level, wherein PC produced around 71.97% of 3-DMC. Supplementary studies with the strain B. endophyticus PC proved the adverse effects of colchicine on the metabolic and structural portrait of cells. There was major variance in the cell shape and size, including the clipping of thickness of plasma membrane and cell wall. The number of polyhydroxybutyrate (PHB) rich inclusion bodies were found to be enhanced, suggesting their portrayal in activation of P450-BM3 enzyme which initiates demethylation.
