In silico Investigations of Al2O3 and NiO Nanoparticles Interactions with Antioxidant Enzymes of Fresh Water Fish O.mossambicus

Metal oxide nanoparticles caused hazardous to aquatic organisms, especially fishes. Nanomaterials of Aluminium and nickel oxide are applied in wide range of applications. However the toxicity of these metal oxide nanoparticles on freshwater fish is very scarce. In this study, we investigated the toxic impact of these two nanoparticles through an in silico approach. The antioxidant enzymes /proteins of SOD, CAT and GST in fish O.mossambicus were docked against Al2O3 and NiO NPs. These enzymes are responsible for oxidative metabolism of a large number of nanomaterials. Induction of oxidative stress by NPs exposure leads to inhibition of these enzymes. The targeted proteins SOD, CAT and GST were retrieved from Alpha fold database and docked with ligands. Molecular docking was conducted using CB - Dock and AutoDock Vina software tools to find the binding affinity and interaction with amino acids of each protein. The target proteins found to strongly interact with ligands through hydrogen bonding and metal coordination interactions. The lowest binding energy shows strong binding of ligands with proteins. Docking results revealed that the amino acids residues of SOD, CAT and GST enzymes are strongly bind with the Al2O3 and NiO NPs in its active site and causes inhibition of the enzymes activities. CAT exhibited lowest binding affinity of (-4.0 Kcal/mol) among all enzymes and significantly inhibited by NiO NPs, followed by GST (-3.4 Kcal/mol), likewise CAT (-1.7 Kcal/mol) and GST (-1.8 Kcal/mol) was moderately inhibited by Al2O3 NPs. SOD inhibited insignificantly by both the NPs. In conclusion, NiO NPs effectively inhibit antioxidant enzymes activity than Al2O3 NPs.