In silico analyses of Cj0983- and Cj0090-derived epitopes for Campylobacter jejuni vaccine applications

Date of Completion

2023

Document Type

Thesis

Degree Name

Bachelor of Science in Biochemistry

Keywords

Campylobacter jejuni, bacterial vaccines, antigenic, allergenic, peptide epitopes, immunity

Abstract

The emergence of antimicrobial resistance has been of growing major concern in both developed and developing countries. As a result, alternative approaches such as ongoing research on bacterial vaccines has played a pivotal role in mitigating bacterial public health concerns. Campylobacter jejuni, a Gram-negative bacterium, is the major etiologic agent of campylobacteriosis which is responsible for most global foodborne illnesses, including cases of erythromycin- and fluoroquinolone-resistant C. jejuni infections. Therefore, the demand for the development of bacterial vaccines is increasing. Although there are ongoing studies on the development of vaccine candidates based on structurally elucidated antigenic proteins of C. jejuni, the potential of Cj0983 and Cj0090 to be independently considered in the preparation and expansion of a protective lipoprotein antigen-based C. jejuni vaccine remain elusive. The general objective of the study is to determine the potential antigenic epitopes in Cj0983 and Cj0090 from C. jejuni for possible vaccine applications. The physicochemical properties of Cj0983 and Cj0090 were assessed using ProtParam and PONDR, revealing Cj0983 as a stable protein while Cj0090 contains few disordered protein regions. The peptide epitopes were identified and evaluated for their antigenic and allergenic properties using VaxiJen and AllergenFP, respectively. In silico analyses revealed that there were 37 B-cell, 371 Class I T-cell, and 365 Class II T-cell epitopes found from Cj0983 while there were 10 B-cell, 63 Class I T-cell, and 93 Class II T-cell epitopes found from Cj0090. PyMOL screened and predicted selected molecular interactions in between chains of HLA-peptide epitope complexes, revealing that H-bonding is the most predominant intermolecular force during binding. Our results identified the top three epitopes for Cj0983 (312QNDDYKLNLDLKFKN326, 311TQNDDYKLNLDLKFK325, and 309NITQNDDYKLNLDLKF324) and Cj0090 (98QEVILRKLASDTRAND113, 106ASDTRANDFRLEIKA120, and 113DFRLEIKAK121) which have great potentials as C. jejuni vaccine components. Further research should focus on the capability of these identified peptide epitopes to be immunogenic and induce host immunity as a contributing knowledge towards advancing anti-C. jejuni vaccine development.

First Advisor

Nedrick T. Distor

This document is currently not available here.

Share

COinS