A molecular docking simulation study on potent inhibitors against Rhizoctonia solani and Magnaporthe oryzae in rice: silver-tetrylene and bis-silver-tetrylene complexes vs. validamycin and tricyclazole pesticides

Abstract

Rice, well known as the most important staple food source worldwide, is highly susceptible to many infectious diseases, especially rice sheath blight caused by fungus Rhizoctonia solani and rice blast caused by fungus Magnaporthe oryzae. The inhibitory ability of silver- and bis-silver-tetrylene complexes, including Ag-E and bis-Ag-E with E = C, Si, Ge, onto protein 4G9M in Rhizoctonia solani and protein 6JBR in Magnaporthe oryzae was theoretically investigated using molecular docking simulation methodology. Two commercial pesticides selected as inhibitory references are validamycin for 4G9M and tricyclazole for 6JBR. The results reveal that bis-silver-tetrylene complexes perform the strongest inhibitory effects towards both proteins. The structures of the complexes exhibit good site–site binding to both proteins given the observations on the hydrogen bond interactions, cation–π bonds, π–π bonds, and ionic interactions, interaction distance between amino acids and ligands, and van der Waals interactions. The inhibitory capacity onto protein 4G9M decreases in the following order: bis-Ag-C > bis-Ag-Si > bis-Ag-Ge > validamycin > Ag-C ≈ Ag-Si ≈ Ag-Ge. The corresponding order observed from the study for protein 6JBR is bis-Ag-C > bis-Ag-Si ≈ bis-Ag-Ge > tricyclazole ≈ Ag-C ≈ Ag-Si ≈ Ag-Ge. The study opens a promising approach to tackle rice blast and rice sheath blight based on a family of silver-tetrylene organometallic chemicals given the theoretical proof of environment-advanced properties and molecule-scaled effectiveness.