In-silico functional annotation of a hypothetical protein from Edwardsiella tarda revealed Proline metabolism and apoptosis in fish

Abstract

Edwardsiella tarda is one of the most widespread pathogens in aquatic species. A wide variety of diseases can be caused by this microbe, including Edwardsiella septicaemia but clinical signs of infection differ between species of fish. The fact that the bacteria is resistant to a wide range of antimicrobials is extremely important. Furthermore, several proteins in its genome are classified as hypothetical proteins (HPs). As a result, the current work sought to elucidate the roles of a HP found in the genome of E.tarda. To determine the structure and function of this protein, many bioinformatics methods were used. To locate the homologous protein, the sequence similarity was searched across the available bioinformatics databases. Quality evaluation methods were used to predict and confirm the secondary and tertiary structure. Additionally, the active site and interacting proteins were examined using CASTp and the STRING server. An important biological activity of the HP is that it contains single functional domains that may be responsible for host-cell invasion and autolysis. Further, protein-protein interactions within selected HP revealed several functional partners that are essential for bacterial survival. One such partner is the proline dehydrogenase/delta-1-pyrroline-5-carboxylate dehydrogenase (putA) of E. tarda. In addition, molecular docking and simulation results showed stable bonding between HP and Proline metabolism protein. Finally, the current work shows that the annotated HP is associated with possible mitochondrial metabolism and autolysis formation activities, as well as having a stable binding with the putA protein, which might be of significant relevance to future bacterial genetics research.