A molecular docking study between heavy metals and hydrophilic Hsp70 protein to explore binding pockets

Microorganisms are abundant in whole biosphere and exert influential activities on numerous biological phenomena. The source of heavy metal contaminants includes both industrial and anthropogenic products. Heavy metal pollution is now a prime concern for the whole world including India. Non-essential minerals like cadmium (Cd) and lead (Pb) are responsible for damage of vital organs in higher concentrations. Remediation of pollutant is required to clean up society. Over the period of time, different physical and chemical methods are used to remove heavy metals but rendered as inefficient because of uneconomical cost and generation of chemical waste. Microbial bioremediation, particularly the use of bacteria, gained significant attention in the removal of contaminants. Bacteria and archaea secrete some special proteins like Hsp70 to resist stress conditions and functions in the removal of heavy metals. Archaeal and bacterial Hsp70 protein sequences were retrieved and named as BHSP70 to explore and analyze physico-chemical parameters, domain, motifs, conserved residue, and antigenicity. 3D structure and quality of each protein were predicted and validated. BHSP70-114 of Sulfobacillus acidophilus was selected for metal docking study to visualize multi-metal resistance capabilities. Docking model of BHSP70-114 with heavy metals was generated with Biovia Discovery Studio to inspect the intramolecular interactions. In this study, amino acid residues like Arg 51, Asp52, Thr 54, Gln 55, Ala 99, Ala 228, and Glu 232 were recognized to involved in heavy metal (Cd, Pb) binding. In addition, this in silico approach explores protein engineering for optimum use of Hsp70 protein to remove heavy metals from biosphere.