Table 1.

Examples of some important virulence factors and their roles in C. jejuni.

Virulence factors	C. jejuni gene, protein, or component	Role	References
Stress response	CosR GroESL DnaJ Lon protease RacR-RacS	Oxidative stress response regulator Heat shock operon Heat shock protein Heat shock protein Regulate temperature during growth and colonization	(Hwang et al., 2011) (Thies et al., 1999) (Konkel et al., 1998) (Thies et al., 1999) (Brás et al., 1999)
Motility and chemotaxis	fliA ropN FlgR,S CheA, B, R, W, V, Y CheY	Flagellar (sigma 28) → regulates the transcription of flagellar genes Flagellar (sigma 54) → regulates the transcription of flagellar genes Regulate the flagellum protein biosynthesis Chemotaxis signal transduction (Che) proteins network. Response regulator used for flagellar rotation	(Jagannathan et al., 2001) (Jagannathan et al., 2001) (Hendrixson, 2006) (Chandrashekhar et al., 2017) (Yao et al., 1997)
Adhesion	RacR-RacS LOS CadF	Persistent colonization of the gut. Involved in adherence and display molecular mimicry of neuronal ganglioside → Guillain-Barré syndrome Fibronectin-binding outer membrane protein	(Van der Stel et al., 2015) (Young et al., 2007) (Konkel et al., 1997)
Invasion	Flagellum LOS CPS Cia	Non-flagellated mutants are less invasive. Lipopolysaccharide → Involved in invasion Capsular polysaccharide → Involved in invasion Invasive antigens	(Konkel et al., 1999b) (Grant et al., 1993) (Karlyshev and Wren, 2001) (Rivera-Amill et al., 2001)
Secretion	pVir CiaB	Plasmid found in some C. jejuni isolates led to type IV secretion system. Play role in invasion and type III secretion system	(Bacon et al., 2002) (Konkel et al., 1999a; Konkel et al., 1999b)
Toxins	CdtA, B, C (Cytolethal distending toxin)	Cell distension, cell cycle block and DNA damage → Cell death.	(Lara-Tejero and Galán, 2001)