The expression of msbA in 11 clinical isolates. (A) Slot blots analysis of msbA expression in 11 clinical isolates. Hybridization was performed with DIG probes specific for 23S rRNA and msbA. (+) represents glutaraldehyde treatment. (-) represents no glutaraldehyde treatment. (B) Bacteria were treated or not treated with glutaraldehyde by three independent experiments. The RNA ratio (msbA/23S rRNA) without glutaraldehyde treatment was defined as 1, and the RNA ratio with glutaraldehyde treatment was calculated.