Effect of detergents on pathogenicity plasmids of escherichias.

The study dealth with effects of cationic detergents miramistin (alkylamidopropyldimethylbenzylammonium chloride), catamine AB (alkyldimethylbenzylammonium chloride) and the anionic compound sodium dodecyl sulphate (SDS) on the elimination from E. coli cells of plasmids determining the Hly, Ent and, indirectly, Col, F, and R markers of pathogenicity as well as their transfer upon conjugation. At subbacteriostatic concentrations, miramistin and catamine AB were found to suppress the transfer of Hly, Ent, F, and R plasmids during conjugation when applied to the donor, recipient or added to the conjugation medium without, however, eliminating plasmids. This is due to the disruption by detergents of F, J pili and other surface cell structures resulting in diminished ability to conjugate. Anionic SDS eliminated F and R plasmids without affecting Hly, Ent and Col.