Restoring virulence to mutants lacking subunits of multiprotein machines: functional complementation of a Brucella virB5 mutant

Nicolas Sprynski (1) , Christine Felix (1) , David O’callaghan (1) , Annette C Vergunst (1)

1 VBMI - Virulence bactérienne et maladies infectieuses

Complementation for virulence of a non-polar virB5 mutant in Brucella suis 1330 was not possible using a pBBR-based plasmid but was with low copy vector pGL10. Presence of the pBBR-based rep-licon in wildtype B. suis had a dominant negative effect, leading to complete attenuation in J774 macrophages. This was due to pleiotropic effects on VirB protein expression due to multiple copies of the virB promoter region and over expression of VirB5. Functional complementation of mutants in individual components of multiprotein complexes such as bacterial secretion systems, are often problematic; this study highlights the importance of using a low copy vector.

Domaines: Sciences du Vivant [q-bio]; Microbiologie et Parasitologie; Bactériologie

Nicolas Sprynski, Christine Felix, David O’callaghan, Annette C Vergunst. Restoring virulence to mutants lacking subunits of multiprotein machines: functional complementation of a Brucella virB5 mutant. FEBS Open Bio, 2012, 2 (1), pp.71-75. ⟨10.1016/j.fob.2012.03.003⟩. ⟨hal-02381142⟩