Two-Way Bacterial Detoxifiers Obtained from Naturally Boron-Rich Sediments in Türkiye: a Study on Intracellular Boron Accumulation and Arsenite Biotransformation

Boron and arsenic are elements that can acquire harmful quantities as a result of both natural and human activity. This research assessed boron tolerance, intracellular boron accumulation, resistance to arsenite [As(III)] and arsenate [As(V)], arsenite transformation capabilities, and genetic characterization of 31 strains taken from Turkey, a country noted for its high boron concentration. Experimental testing indicated that the majority of the strains exhibited tolerance to boron dosages of 150-200 mM, while a minority tolerated levels of 250-300 mM. In the intracellular boron accumulation experiments, strains 8 (1.32 +/- 0.05 mg/L) and 31 (0.94 +/- 0.03 mg/L) from the Lysinibacillus genus displayed high activity. The MIC and MBC techniques for both arsenite and arsenate were applied to assess the resistance state. Furthermore, five species, including strain 8 from the genus Lysinibacillus, were discovered to oxidize As(III) to As(V). Furthermore, aioA, a gene implicated in arsenite oxidation, was tested via PCR; however, it was not discovered in any of the strains. Nonetheless, the transformation of As(III) was phenotypically verified using a colorimetric approach. Phylogenetic analysis based on 16S rRNA and AFLP data was also performed and indicated that most bacteria belonged to the genera Lysinibacillus and Bacillus, while a few were firmly connected to Enterobacter and Enterococcus. The findings suggested that strain 8, a member of Lysinibacillus spp., is a promising candidate indigenous strain for bioremediation purposes to detoxify settings abundant in boron minerals from excess boron and arsenic.