In sillico binding affinity studies of microbial enzymatic degradation of plastics

•Manganese peroxidase enzyme showed the best degradation for all studied plastics.•The binding amino acid residues mainly include arginine, leucine and serine for all plastics.•The interactions involved Van der Waals, conventional hydrogen bonding, carbon-hydrogen bond and Pi- Interactions.•Cluster analysis suggests similar degradation pathways for some specific plastic types. Numerous recent research have shown that a variety of microbes and enzymes are capable of decomposing synthetic plastics. To verify the usage of these enzymes in plastic breakdown, in silico investigation of the binding affinity of common plastic compounds [polyamide (PA), poly vinyl chloride (PVC), polycarbonate (PC), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA) and polyurethane (PUR)] to several enzymes such as lipase, carboxylesterase, lignin peroxidase, copper dependent laccase, alkane hydroxylases and manganese peroxidase was conducted. The multiple ligand molecular simulations of the plastic compounds docked on the enzyme targets was done with Autodock Vina in PyRx software version 0.8. Aside from observing for active site interaction between the enzyme-substrates complexes, other parameters such as the highest binding affinity, hydrophobic interactions, and hydrogen bonds were also investigated. Results showed that based on binding affinity, manganese peroxidase showed the best degradation for all plastic types in the order PVC (- 2.7 kcal/mol) < PMMA/PUR (- 4.7 kcal/mol) < PA (-7.5 kcal/mol) < PET (-7.8 kcal/mol) < PC (- 9.1 kcal/mol). The binding amino acid residues mainly include arginine, leucine and serine for all plastics while the interactions involved Van der Waals, conventional hydrogen bonding, carbon-hydrogen bond and Pi- Interactions. Cluster analysis on the basis of their response to enzyme attack showed two cluster groups A and B. Cluster A includes three plastics (PMMA, PUR and PVC), while cluster B also comprises three plastics (PA, PET and PC), suggesting similar degradation pathways. The study demonstrated the potential use of these enzymes for the degradation of plastics. [Display omitted]