Experimental production of colicin type V of Shigella sonnei unusual in nature.

Col V factor of Fredericq's strain Escherichia coli 1.7a was mobilized for a transfer by the R (Sm, Cm, Tc, Su) factor of Shigella sonnei strain in three component test. The strain E. coli K13 HfrR (a universal indicator for evidence of colicinogeny) and S. sonnei strain became the recipient of both plasmids. S. sonnei, a producer of colicin V has not been found in natural conditions as yet.