Studies on the Transfer of the Fimbriation between Escherichia coli and Shigella flexneri

Mutual transfer of the fimbriation from the fimbriate donor cells to the non-fimbriate recipient cells was demonstrated in the selected recipient hybrids from the crosses between E. coli and Sh. flexneri.In the recipient hybrids which have been transferred the ability of the fimbriation, there were shown some biological characteristics different from the parent recipient cells, from which the hybrids were originated, in addition to the alteration of the antigenic structure and the modification of sugar fermentation, which were transferred from the parent donor cells, the dissociation of the colony form was clearly observed.Further observations on the segregations of the hybrids presented an evidence suggesting that the transfer of the ability of fimbriation might be due to the genetic recombination of fimbriation controlling gene(s), probably episome-like in nature, and that the recipient fimbriate hybrids seemed to be heterogenous in genotype.