Type III secretion needle tip protein PcrV (PcrV)

Type III secretion needle tip protein PcrV is a hydrophilic protein located at the tip of the type III secretion system (T3SS) needle in *Pseudomonas aeruginosa*[2][3][5]. It is an essential component of the translocation apparatus, connecting the secretion needle to the host cell membrane and forming a scaffold for the correct insertion of translocator proteins PopB and PopD, which together create a pore through which effector toxins are injected into host cells[2][5][7]. PcrV is indispensable for T3SS function and pathogen virulence, and it also has a proinflammatory role, activating M1 macrophages and reducing biofilm burden during infection[1]. Anti-PcrV monoclonal antibodies and PcrV-based vaccines block pore formation and toxin injection, making PcrV a validated therapeutic target for passive and active immunotherapies designed to combat acute and chronic *P. aeruginosa* infections[1][3][5].

Other names

V-antigen (in the context of Pseudomonas aeruginosa)PcrV protein

Blockade of toxin injection via T3SS inhibition (antibody-mediated); Induction of host immune responses (vaccine-mediated); Inhibition of translocon formation