Immunoinformatics-based design and evaluation of a multi-epitope vaccine against Vibrio fluvialis
Muhammad Naveed, Muhammad Husnain, Tariq Aziz, Parveen Qadir, Muhammad Asim, Muhammad Nouman Majeed, Abeer S. Aloufi, Ashwag Shami, Maher S. Alwethynani, Nantenaina Tombozara
Abstract
Vibrio fluvialis is an emerging foodborne pathogen causing gastroenteritis and extraintestinal infections, representing a significant public health concern due to rising antimicrobial resistance and the absence of an approved vaccine. This study aimed to design a multi-epitope subunit vaccine against V. fluvialis using immunoinformatics and a standard multi-epitope vaccine design pipeline. Two surface-exposed immunogenic membrane proteins, ATP-dependent zinc metalloprotease FtsH and lytic murein transglycosylase F, were selected as antigenic targets. Ten epitopes, including four MHC class I, four MHC class II, and two B-cell epitopes, were predicted and assembled into a 246 amino acid vaccine construct. The construct showed an antigenicity score of 0.8610. Population coverage analysis indicated that these epitopes could potentially cover 99.97% of the global population. The vaccine exhibited favorable physicochemical properties, with an instability index of 33.18 and a GRAVY score of - 0.282, suggesting stability and hydrophilicity. The tertiary structure was modeled using AlphaFold3 and docked with Toll-like receptor 2, yielding a docking score of - 270.01. Molecular dynamics simulations for 100 ns suggested stability of the vaccine-TLR2 complex. Codon optimization indicated high expression potential in Escherichia coli, with a CAI value of 0.95. Overall, the vaccine showed strong in silico immunogenic potential and requires further experimental validation through in vitro and in vivo studies.