Yersinia enterocolitica is an opportunistic pathogen which causes enteric diseases like gastroenteritis and mesenteric adenitis in immune-compromised individuals. The gastrointestinal phase of Y. enterocolitica infection is mediated by Yersinia secretion apparatus - Yersinia secretion protein (Ysa-Ysp) Type III Secretion System (T3SS). Enhanced virulence of Y. enterocolitica Biovar 1B is attributed to the activation of Ysa-Ysp T3SS, which is further regulated by the formation of functional injectisome. YspB and YspC are hydrophobic translocator proteins which are responsible for the formation of functional translocon at the tip of the needle complex. These translocators are sequestered in the bacterial cytoplasm by their cognate chaperone SycB. SycB plays the dual role of a class II chaperone and a regulator of Ysa-Ysp T3SS. Homology model of SycB depicts a structure with a concave core formed by tetratricopeptide repeats (TPRs) and a flexible N-terminal helix. Deletion mutants of SycB showed that the N-terminal helix of SycB is responsible for its dimerization, which is further corroborated by molecular docking analysis.
