| Autor: |
Vitasovic T; Interdisciplinary Nanoscience Center (iNANO), Faculty of Natural Sciences, Aarhus University, Gustav Wieds Vej 1590-14, 8000 Aarhus C, Denmark.; Aarhus University Center for Water Technology (WATEC), Aarhus University, Ny Munkegade 120, 8000 Aarhus C, Denmark., Caniglia G; Institute of Analytical and Bioanalytical Chemistry, Ulm University, Albert Einstein Allee 11, 89081 Ulm, Germany., Eghtesadi N; Interdisciplinary Nanoscience Center (iNANO), Faculty of Natural Sciences, Aarhus University, Gustav Wieds Vej 1590-14, 8000 Aarhus C, Denmark.; Chemical Engineering Department, Nazarbayev University, 53 Kabanbay Batyr Avenue, Nur-Sultan 01000, Kazakhstan., Ceccato M; Interdisciplinary Nanoscience Center (iNANO), Faculty of Natural Sciences, Aarhus University, Gustav Wieds Vej 1590-14, 8000 Aarhus C, Denmark., Bo Jesen ED; Interdisciplinary Nanoscience Center (iNANO), Faculty of Natural Sciences, Aarhus University, Gustav Wieds Vej 1590-14, 8000 Aarhus C, Denmark., Gosewinkel U; Department of Environmental Science, Aarhus University, Frederiksborgvej 399, DK-4000 Roskilde, Denmark., Neusser G; Institute of Analytical and Bioanalytical Chemistry, Ulm University, Albert Einstein Allee 11, 89081 Ulm, Germany., Rupp U; Central Facility for Electron Microscopy, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany., Walther P; Central Facility for Electron Microscopy, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany., Kranz C; Institute of Analytical and Bioanalytical Chemistry, Ulm University, Albert Einstein Allee 11, 89081 Ulm, Germany., Ferapontova EE; Interdisciplinary Nanoscience Center (iNANO), Faculty of Natural Sciences, Aarhus University, Gustav Wieds Vej 1590-14, 8000 Aarhus C, Denmark.; Aarhus University Center for Water Technology (WATEC), Aarhus University, Ny Munkegade 120, 8000 Aarhus C, Denmark. |
| Abstrakt: |
Antibacterial formulations based on zinc oxide nanoparticles (ZnO NPs) are widely used for antibiotic replacement in veterinary medicine and animal nutrition. However, the undesired environmental impact of ZnO NPs triggers a search for alternative, environmentally safer solutions. Here, we show that Zn 2+ in its ionic form is a more eco-friendly antibacterial, and its biocidal action rivals that of ZnO NPs (<100 nm size), with a minimal biocidal concentration being 41(82) μg mL -1 vs 5 μg mL -1 of ZnO NPs, as determined for 10 3 (10 6 ) CFU mL -1 E. coli . We demonstrate that the biocidal activity of Zn 2+ ions is primarily associated with their uptake by E. coli and spontaneous in vivo transformation into insoluble ZnO nanocomposites at an internal bacterial pH of 7.7. Formed in vivo nanocomposite then damages E. coli membrane and intracellular components from the inside, by forming insoluble biocomposites, whose formation can also trigger ZnO characteristic reactions damaging the cells (e.g., by generation of high-potential reactive oxygen species). Our study defines a special route in which Zn 2+ metal ions induce the death of bacterial cells, which might be common to other metal ions capable of forming semiconductor oxides and insoluble hydroxides at a slightly alkaline intracellular pH of some bacteria. |
