Functional Annotation of Uncharacterized Protein from Photobacterium damselae subsp. piscicida (Pasteurella piscicida) and Comparison of Drug Target Between Conventional Medicine and Phytochemical Compound Against Disease Treatment in Fish: An In-silico Approach

Photobacterium damselae is one of the deadliest bacterial pathogens in the world of aquaculture. P. damselae has an uncharacterized protein (UniprotKb ID: A0PB24) that can enter the host cell and induce infection in fish, according to research. Domains of unknown function are proteins that have been identified experimentally but do not have a known functional or structural domain. Targeting this uncharacterized protein, we found that this protein may have link with other virulent proteins of P. damselae. So, the main objective of the study was to reveal the functional annotation of the protein and compare the inhibitory potentiality of conventional drug (Flumequine, Oxytetracycline and Florfenicol) and four potential antibacterial compounds from Syzygium aromaticum which reported previously. The uncharacterized protein was modeled, refined, and validated in this experiment. The protein-protein interaction network suggested that this uncharacterized protein may serve as a DNA/RNA hydrase and conserved domain search predict two different domains. Furthermore, the binding affinity of conventional drugs and phytochemical compounds were calculated against the protein with the docking approaches and predict S. aromaticum inhibitory compounds bind strongly with the protein. In addition, the ADMET properties of the compounds confirmed the drug likeness properties of the four compounds.