Hcp2b of T6SS affects colonization of avian pathogenicand host keratin filament expression.

Abstract

T6SS (type VI secretion system) is a type of nano-syringe that exists in APEC (avian pathogenic). Hcp (haemolysin-coregulated protein) of T6SS participates in the regulation of virulence during APEC infection. However, whetherplays a role in bacterial colonization by expression in host cells remains unclear. In this study, we analysed the biological characteristics of the mutantstrain. Our results showed that thegene was involved in the regulation of bacterial motility, biofilm formation, anti-serum and anti-oxidative stress. Moreover, our data indicate that the colonization of themutation strain (Δ) in the lung, liver and kidney of chickens decreased significantly. Hence, overexpression of Hcp2b protein in DF-1 cells was used to analyse the effect of Hcp2b on colonization of APEC. Proteomics analysis showed that overexpression of Hcp2b induced differentially expressed proteins in DF-1 cells (230 were significantly upregulated and 96 were significantly downregulated) and differentially expressed proteins were enriched in keratin filament. In conclusion, our data indicated thatpromoted the colonization of APEC by affecting the expression of keratin filament.