3-Deoxy-3-fluoro-D-glucose-resistant Salmonella typhimurium mutants defective in the phosphoenolpyruvate:glycose...

Three classes of phosphotransferase system mutants in Salmonella typhimurium were selected through their resistance to 3-deoxy-3-fluoro-D-glucose (DFG). Strains with mutations in the ptsH (HPr) and/or pts I (enzyme I) genes were selected on medium containing lactate plus DFG. Strains with mutations in ptsH but not pstI were selected on medium containing fructose plus DFG. Clones isolated from fructose plus DFG semisolid plates and selected for ability to swarm were mutant in either ptsH or ptsG. Mutants of the latter class were defective in enzyme IIB', a membrane component of the glucose transport system. Some pleiotropic properties of one representative ptsG mutant are described.