ABSTRACTThe haemolysin co-regulatory protein (Hcp) plays a significant role in the pathogenicity of avian pathogenic Escherichia coli (APEC) as an effector protein of the type VI secretion system (T6SS) to the host. Meanwhile, mitochondria in host have become the target of effector proteins of various secretion systems. Here, we wanted to explore the effects of APEC effector Hcp2b on the mitochondria of DF-1 cells, and found that Hcp2b results in a damage in mitochondria. Next, 68 target proteins in DF-1 cell lysates were identified that interacted with Hcp2b by streptavidin-biotin pull-down assay combined with LC-MS/MS, among which, ADP/ATP transporter carrier (SLC25A4) is a mitochondria-associated protein and protein docking analysis showed that Hcp2b binds well to SLC25A4. Therefore, we hypothesize that the Hcp2b contribute to mitochondrial damage through interaction with the SLC25A4 in DF-1 cells.
Keywords: Avian pathogenic Escherichia coli; DF-1 cells; Hcp2b; Mitochondrial damage; SLC25A4; T6SS.