Cloning, Expression, and Bioinformatics Analysis of Heavy Metal Resistance Gene afe_1862 from Acidithiobacillus ferrooxidans L1 in Escherichia coli

Molecular studies of copper and cadmium resistances in acidophilic bacteria are significant in biomining. In this study, afe_1862, which encodes a heavy metal-binding protein in Acidithiobacillus ferrooxidans L1, was amplified using PCR, cloned into the pET32a plasmid, and sequenced. Following SDS-PAGE analysis, optimization of the expression conditions and heterologous overexpression of afe_1862 in Escherichia coli BL21 in the presence of Cu2+ and Cd2+ were studied as well. The results indicated that AFE_1862 has higher resistance to Cu2+ than Cd2+. Bioinformatics analysis illustrated that AFE_1862 has a conserved HMA domain containing heavy metal-binding sites, which may play a role in transporting or detoxifying heavy metals.