[Shigella flexneri mutation giving rise to the appearance of fosfomycin-resistant avirulent forms with disordered...

The present work analyzes pt44 mutation in Sh. flexneri resulting in the appearance of the following phenotypical properties: resistance to phosphomycin, avirulence, pleiotropic disturbances in carbohydrate utilization. The data provided by the biochemical and genetic analysis have indicated that pts44 mutation occupies the region between purC and ptsI loci on the chromosome of Sh. flexneri. Merodiploids containing the mutant allele pts44 and the plasmid including purC-ptsI-ptsH genes from E. coli K12 acquired the capacity for fermenting carbohydrates, but at the same time retained resistance to phosphomycin and avirulent properties. The presence of phosphoenol pyruvate-dependent carbohydrate phosphotransferase system in Sh. flexneri has been proved.