Effect of subinhibitory concentrations of some quinolones on a strain of Shigella dysenteriae type 1.

Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) revealed that the outer membrane proteins of a strain of Shigella dysenteriae exposed to four quinolone compounds (ciprofloxacin--CAS 85721-33-1, ofloxacin--CAS 83380-47-6, pefloxacin--CAS 70458-95-6, and enoxacin--CAS 74011-58-8) at subinhibitory concentrations of 1/4 or 1/8 of the minimal inhibitory concentration (MIC) showed no alterations as compared to the control. Also the hydrophobicity of the cell surface of the test strain was not affected after exposure to subinhibitory concentrations of the quinolones.