P. aeruginosa strains vary in their ability to develop BLS in ASM+. P. aeruginosa strains PAK, PA103, and CI-4 (a clinical isolate) were transformed with pMRP9-1. The strains, plus PAO1/pMRP9-1, were grown in ASM+ under 10% EO2 without shaking for 3 d. The BLS were analyzed as described in Figure 3. (A) CLSM micrographs of the BLS; magnification, 10X; bar, 200.00 nm. (B) The 3-D architecture of the BLS shown in (A); boxes, 800.00 px W x 600 px H; bars, 100 px.