[Electrophysical analysis of Escherichia coli cell damage caused by silver ions].
The influence of Ag+ (0.5-10 microM) on Escherichia coli K-12 cells was studied by electrophoresis and electro-orientation spectroscopy methods. It was shown that the pH-dependency of the cell electrokinetic potential (phosphate-citrate buffer with ion strength 0.02) practically didn't changed after Ag+ treatment, but in low-conductive media electrophoretical mobility of intact and inactivated by heat (70 degrees, 15 min) cells gradually decreased as the Ag+ concentration increased. It was due to the Ag+ adsorption on the cell surface and could not be used for the definite characterization of the cell damage. The high-frequency decrease in the cell electro-orientation spectrum shifted to the region of lower frequencies, K+ was excreted by cells, slight raise of the medium pH occurred and significant changes of cell osmotic properties were observed as a result of Ag+ action. All these changes showed the disturbance of barrier properties of the cytoplasmic membrane. Besides the damaging action of Ag+ on cell membranes increased with the decrease of pH and decreased after the addition of Mg2+, Ca2+ and Sr2+ in low concentrations.
Ivanov
A Iu
AIu
Fomchenkov
V M
VM
D000327:Adsorption; D002414:Cations, Monovalent / Q000493:pharmacokinetics / Q000494:pharmacology; D002462:Cell Membrane / Q000378:metabolism; D004586:Electrophoresis; D004926:Escherichia coli / Q000187:drug effects* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D012834:Silver / Q000633:toxicity*; D013057:Spectrum Analysis / Q000379:methods
D002414:Cations, Monovalent; D012834:Silver
Elektrofizicheskiĭ analiz povrezhdeniia bakterial'nykh kletok Escherichia coli ionami serebra.