Fig 3. Diffusion assays carried out with the biosensor Chromobacterium violaceum CV026 to detect the presence of QQ activity in the clinical strains of A. baumannii under study.

The presence of a halo indicates inhibition of violacein production by the presence of 3-oxo-C12-HSL and, therefore, the absence of QQ activity (a, h). The absence of a halo indicates QQ activity (b, c, d, e, f, g). a) Control; b) Ab1; c) ab2; d) Ab3; e) Ab4; f) Ab5; g) Ab6; h) Ab7.