[Action of various surface-active substances on the genetic transmission of R-plasmids in E. coli]

The effect of 4 groups of surface active-substances (SAS) on conjugation and transduction transfer of plasmid RIdrd from the donor of E. coli J 5-3 to the recipient of E. coli C600 was studied. It was shown that the anionic SAS (8 compounds) had the highest inhibitory effect. They completely inhibited both the conjugation and the transduction transfer of R-plasmids. The amphoteric SAS, i. e. tego-51 and ampholan had the same effect only on the transduction R-transfer. The conjugation R-transfer was inhibited by the above compounds to a significant extent but not completely, i. e. by 70.8 and 361.9 times respectively. The effect of the non-ionogenic preparations, i. e. sintanol DT-7 was even less (the inhibition coefficients of 54.8 and 22.8 on conjuction and transduction respectively). The cationic SAS, i. e. catamine AB and HIPC-200 had no effect on the genetic R-transfer. It was shown that the anionic SAS had a phagocytic effect on phage Plks. It is of interest to note that the anionic SAS, i. e. sintanol NP-3 effectively suppressed the conjugation transfer even in a concentration of 100 gamma/ml which was 1000 times lower than the subbacteriostatic one. The effectiveness of the anionic SAS did not depend on the length of the dydrocarbon chain and was the same in separate homologues and their mixtures. The high inhibitory activity of most of the SAS and especially the anionic ones with respect to both the conjugation and the transduction R-transfer was of interest.