title: Antibacterial activity of silver-killed bacteria: the "zombies" effect.
abstract: We report a previously unrecognized mechanism for the prolonged action of biocidal agents, which we denote as the zombies effect: biocidally-killed bacteria are capable of killing living bacteria. The concept is demonstrated by first killing Pseudomonas aeruginosa PAO1 with silver nitrate and then challenging, with the dead bacteria, a viable culture of the same bacterium: Efficient antibacterial activity of the killed bacteria is observed. A mechanism is suggested in terms of the action of the dead bacteria as a reservoir of silver, which, due to Le-Chatelier's principle, is re-targeted to the living bacteria. Langmuirian behavior, as well as deviations from it, support the proposed mechanism.
authors.affiliation: Institute of Chemistry and the Center for Nanoscience and Nanotechnology, the Hebrew University of Jerusalem, Jerusalem 91904, Israel.
authors.forename: Racheli Ben-Knaz
authors.initials: RB
authors.lastname: Wakshlak
authors.affiliation: 1] Institute of Chemistry and the Center for Nanoscience and Nanotechnology, the Hebrew University of Jerusalem, Jerusalem 91904, Israel [2] Department of Environmental Health, Hadassah Academic College, Jerusalem 91010, Israel.
authors.forename: Rami
authors.initials: R
authors.lastname: Pedahzur
authors.affiliation: Institute of Chemistry and the Center for Nanoscience and Nanotechnology, the Hebrew University of Jerusalem, Jerusalem 91904, Israel.
authors.forename: David
authors.initials: D
authors.lastname: Avnir
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D013058:Mass Spectrometry; D046529:Microscopy, Electron, Transmission; D011550:Pseudomonas aeruginosa / Q000187:drug effects*; D012835:Silver Nitrate / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D012835:Silver Nitrate