Structural and functional insights into fungal glutaminase using a computational approach

Fungal glutaminases are significant among microbial glutaminases due to their current and potential industrial applications. They have been found useful as food flavoring agents, biosensor components, and various therapeutic applications. Despite these notable applications, little is known about their structural characteristics, which is vital in understanding their biological function and industrial applicability. The objectives of this study include the elucidation of the primary and secondary structures, as well as the physicochemical properties, of forty-four fungal glutaminases utilizing readily available and widely used in silico tools. The physicochemical analyses predicted that the computed fungal glutaminases’ average sequence length was ~680 amino acid residues. All of the glutaminases were predicted to be extracellular, have acidic pIs, hydrophilic, and highly stable. The 3D models of four representative fungal glutaminases were predicted, refined, and validated using various online servers. Docking studies revealed similar interactions for the evaluated glutaminases and the ligand (DON), which was validated by MD simulation. The simulation of the docked glutaminase-DON complexes also demonstrated their significant structural stability in a dynamic environment. Information from this study would be useful as a reference for future wet lab studies and endeavors such as the engineering of glutaminase enzymes for enhanced capabilities and developing possible drugs and fungicides targeting fungal glutaminases.