In silico Identification of Novel Therapeutic Targets and Epitopes among the Essential Hypothetical Protein of Pseudomonas aeruginosa: A Novel Approach for Antivirulence Therapy

Abstract

Abstract Background. Pseudomonas aeruginosa is a critical pathogen that represents a challenge in healthcare due to its virulence and antibiotic resistance capabilities. The development of new medications and vaccinations is critical. Antivirulence treatment, which exploits virulence factors as pharmacological targets, will emerge as a preferred therapeutic option. P. aeruginosa genome constitutes 335 essential genes, which are vital for pathogens' survival. The functions of 89 proteins encoded by P. aeruginosa essential genes were uncharacterized and thus referred to as essential hypothetical proteins (EHPs). They could eventuate as potential drug and vaccine targets since their deletion or inactivation results in the organism's death. The objective of this work is to use bioinformatics applications and databases to perform functional characterization for the EHPs. Methods. After retrieving the corresponding sequences, the pseudogenes were excluded, and the characterization of 56 hypothetical proteins was performed through the determination of their physiochemical properties, subcellular localization, functional annotation, domain analysis, and structure. Evaluation of the performance of the various tools was conducted using receiver operating characteristic curve analysis and a high average accuracy was obtained. Results. 35 virulence factors were predicted and those with no homology to both human and gut microbiota proteome were considered potential targets and tested for druggability. All the targets were found to be non-druggable with exception of one. They were further classified as vaccine or drug targets according to their location. The identified vaccine targets were tested for antigenicity. Subsequently. From the 5 vaccine targets, the researchers discovered highly conserved and exposed epitope sequences. The vaccine targets' three-dimensional structures were elucidated and validated for quality. Our comprehensive analysis will help to gain a greater understanding of the development of many novel potential therapeutic interventions to defeat Pseudomonas infections