• Using bioinformatics tools to identify genes involved in the virulence of Campylobacter jejuni chemostat-grown to S-nitrosoglutathione
  • Hossein Sahragard,1 Nastaran Asghari Moghaddam,2,* Bita Bakhshi,3
    1. Department of Biology, Central Tehran Branch, Islamic Azad University, Tehran, Iran
    2. Department of Biology, Central Tehran Branch, Islamic Azad University, Tehran, Iran
    3. Department of Bacteriology, Tarbiat Modares University, Tehran, Iran


  • Introduction: Campylobacter jejuni is the leading cause of bacterial foodborne gastroenteritis worldwide and represents a major public health concern. Moreover, an increasing body of evidence suggests a strong association between C. jejuni infection and Guillain-Barré syndrome, a peripheral nervous system disorder characterized by inflammatory demyelination. C. jejuni virulence factors include motility, chemotaxis, adhesion, and invasion.C. jejuni colonizes the small intestine and colon through the use of virulence factors such as motility, chemotaxis, adhesion, and invasion. A 2021 study identified 126 virulence factors in C. jejuni genomes from around the world. Overall, the virulence of C. jejuni is a complex process that involves multiple factors. Identifying the genes and factors involved in C. jejuni virulence is important for understanding the pathogenesis of this bacterium and developing strategies to prevent and treat infections.
  • Methods: The microarray data with the accession IDs GSE5396 were identified, extracted and analyzed by GEO2R online tools and R software. Genes with the highest differential expression were identified using parameters P<0.05 and LogFC>|1|. Subsequently, the expression of the related genes was isolated and for the genes that had an increase in expression, the protein network was predicted by STRING database and visualized with the Gephi software.
  • Results: By identifying different genes that had a significant decrease or increase in expression, it was found that a set of genes (hrcA, clpB, dnaK, grpE) are involved in virulence of C.jejuni. The (hrcA) gene was found to be an intrinsic protein thermosensor that represses its own promoter and the regulatory region controlling the transcription of other genes at temperatures up to 37°C. The (clpB) gene was found to play a vital role in the thermotolerance of Campylobacter spp. The (dnaK) and (grpE) genes were found to be involved in the synthesis and modification of macromolecules. These findings suggest that these genes play important roles in the virulence of C. jejuni and could be potential targets for the development of interventions to prevent and treat infections.
  • Conclusion: Through comprehensive bioinformatics analysis of gene expression data, this study successfully identified differentially expressed genes in C. jejuni when exposed to chemostat-grown by S-nitrosoglutathione. These findings offer valuable insights into the intricate molecular pathways utilized by C. jejuni to sustain its survival, adapt to environmental stressors, and initiate infections. Moreover, this knowledge can contribute to the development of more potent control measures against infections and aid in the design of preventive strategies.
  • Keywords: Campylobacter jejuni, virulence, microarray, bioinformatics analysis, R software