Attaching and effacing pathogens modulate host mitochondrial structure and function.

Area of Science:

• Microbiology
• Cell Biology
• Pathogenesis

Background:

• Enteropathogenic (EPEC) and enterohemorrhagic (EHEC) Escherichia coli are significant human enteric pathogens.
• These bacteria, along with Citrobacter rodentium, are "attaching and effacing" (A/E) pathogens that utilize a type III secretion system (T3SS).
• The T3SS delivers effector proteins into host cells, crucial for bacterial colonization and disease.

Purpose of the Study:

• To provide an overview of host cell alterations induced by A/E pathogens.
• To specifically focus on the impact of bacterial effectors on host cell mitochondria.
• To highlight the critical role of mitochondria in A/E bacterial pathogenesis.

Main Methods:

• Review of in vitro studies detailing effector interactions with mitochondria.
• Analysis of in vivo studies, primarily using the Citrobacter rodentium/mouse model.
• Examination of host cell modifications, including mitochondrial morphology, function, and apoptosis.

Main Results:

• Bacterial effectors directly target mitochondria, altering morphology, oxidative phosphorylation, and ROS production.
• Disruption of mitochondrial membrane potential and induction of intrinsic apoptosis are observed.
• In vivo studies confirm some in vitro findings and suggest broader physiological changes in the intestine.

Conclusions:

• Mitochondrial modifications are a central mechanism by which A/E pathogens cause disease.
• Deciphering effector-mitochondria interactions is essential for understanding pathogenesis.
• Further research is needed to define the mechanistic underpinnings of in vivo mitochondrial alterations.