Extended Data Fig. 2: PVCs can be tagged with external epitope tags without loss of activity.
From: Programmable protein delivery with a bacterial contractile injection system
a, PVCs harbouring Flag–Pvc2 are active in Sf9 cells, indicating sheath contraction (which is necessary for injection of target cells7) is likely not impaired by the addition of the Flag tag on Pvc2. Values are mean ± s.d. with n = 3 biological replicates. Statistical significance was computed using one-way ANOVA with Bonferroni post hoc test; ****P < 0.0001; ns, not significant. b, Contracted Flag-tagged PVCs can be observed in TEM, providing further evidence this tagging strategy does not inhibit sheath contraction. A PVC particle exhibiting a contracted phenotype is indicated with an arrow. Scale bar, 100 nm. c, The connector ___domain between sheath subunits for both T6SS (PDB: 3J9G) and PVC (PDB: 6J0B) contains a flexible N-terminal ___domain (NTD) that likely enables N-terminal Flag-tagging of this protein without loss of sheath contraction. d, The N-terminus of Pvc2 is externally exposed when the PVC is in the extended state (PBDs: 6J0B, 6J0C), enabling IF-based detection of PVC particles containing Flag–Pvc2. The first five residues of Pvc2 are colored green to mark their position in the sheath complex. e, IF signal against PVCs harbouring Flag–Pvc2 (green) decays after 24 h, possibly suggesting this IF method selectively stains for PVCs in the extended state. Scale bar, 50 μm.
