A Vgr protein that is probably part of a type VI secretion system (T6SS). May be required for export of proteins involved in Rhs-mediated cellular contact-dependent growth inhibition (CDI). A double vgrGA-vgrGB deletion inhibits the ability of RhsB to inhibits cell growth. VgrGB alone restores RhsB-mediated cell growth. Belongs to the VgrG protein family.