EscV

EscV is a core component of the bacterial type III secretion system (T3SS) found in several enteric pathogens, including Escherichia coli and Salmonella species. The EscV protein is part of the basal export apparatus that coordinates assembly of the secretion needle and the translocation of effector proteins into host cells. It is typically encoded within the secretion system gene cluster and is considered essential for T3SS function.

EscV is predicted to be an integral inner-membrane protein with a cytoplasmic domain. It interacts with the ATPase EscN and other basal-body components to energize secretion and regulate substrate passage. Through its interactions, EscV contributes to substrate selection, pore formation, and the initiation of translocation, with loss-of-function mutations often abolishing secretion and reducing virulence.

Across Gram-negative bacteria, EscV is conserved as part of the export apparatus, with homologs such as YscV in Yersinia. Structural analyses and mutational studies suggest EscV forms a multimeric scaffold that interfaces with other export components, helping to organize the complex channel that spans the bacterial envelope.

EscV has been studied to understand bacterial virulence mechanisms and as a potential target for anti-virulence therapies. Insights into EscV function advance knowledge of T3SS assembly, regulation, and host–pathogen interactions, contributing to broader efforts to mitigate infections caused by T3SS-dependent pathogens.

See also: Type III secretion system, YscV, EscN, pathogenicity island.