Effects of Detergents and Divalent Cations on the Functioning of Cell Envelopes of Escherichia coli in the Early Stages of Infection with Bacteriophage ϕX174

Abstract

Effects of detergents and divalent cations (Ca²⁺, Mg²⁺) on intact cells and envelope fraction I of Escherichia coli were examined by measuring the eclipse kinetics of bacteriophage ϕX174 and by polyacrylamide gel electrophoresis of cell envelope proteins. Cell envelopes having receptor activity to convert ϕX174 to eclipsed particles (eclipsing activity) were destroyed by cationic detergent cetyl trimethyl ammonium bromide (CTAB) and anionic detergent N-lauroyl sarcosine sodium salt (Sarkosyl), but were not destroyed by many nonionic detergents, such as Triton X-100, Pluronic PI03, Brij 58, Tween 20 and Tween 80 in the presence of divalent cations. However, nonionic detergent Span 80 caused the disruption of cell envelopes in the presence of a low concentration (1 mm) of divalent cations, but not in the presence of a higher concentration (5 mm) of divalent cations. Divalent cations were shown to stabilize the cell envelope structure and to protect the cell envelopes from solubilization by detergents.