Molecular Docking and Dynamics Simulation of Vibrio anguillarum Aspartate Semialdehyde Dehydrogenase with Natural Product Caulerpin

Aquaculture is currently the source of at least 50% of fish consumed worldwide. Microbes pose an immense threat to present day aquaculture industry. Vibrio anguillarum is one of the causative agents of large scale mortality of cultured
marine fishes, especially Asian sea bass (Latescalcarifer). Antibiotic usage to control infection and diseases in aquaculture is the most prevalent choice due to their inexpensiveness and ease of administration. Aspartate β-semialdehyde dehydrogenase (ASADH) is the seminal enzyme involved in the biosynthesis of amino acids including lysine, methionine and threonine. ASADH is found only in microbes and plants, thus making it a hot target for antibiotic drug design and development. Caulerpin is an emerging drug with excellent antiviral, anti-bacterial, cytotoxic and anti-cancer activities. In this study, we used in silicoapproach to test the efficacy of caulerpin against V. anguillarum ASADH (VA). We modelled 3-D structure of VA and docked it with caulerpin. Docking results show that caulerpin binds VA with a high binding energy (-8.5kcal/mol). Molecular dynamics simulations support enzyme inhibitor interactions as evidenced by the RMSD diagrams. We also propose that caulerpin can be used as antibiotic against other microbes considering the homology of ASADH sequence shared among them.