Changes in the biochemical properties of Shigella flexneri la as a result of recombination with Escherichia coli K12.

The fermentative properties of recombinants obtained after conjugation between E. coli K12 HfeC and S. flexneri la Lac Phe mutant were investigated. The recombinants showed the antigenic structure of S. flexneri but their biochemical characteristics differed from the properties typical for this genus. The recombinants were found to acquire the ability to ferment several carbohydrates not degraded by the S. flexneri recipient strain.