Abstract
In this study, we tested the antimicrobial activity of three metal nanoparticles (NPs), ZnO, MgO, and CaO NPs, against Salmonella enterica serovar Enteritidis in liquid medium and on solid surfaces. Out of the three tested metal NPs, ZnO NPs exhibited the most significant antimicrobial effect both in liquid medium and when embedded on solid surfaces. Therefore, we focused on revealing the mechanisms of surface-associated ZnO biocidal activity. Using the global proteome approach, we report that a great majority (79%) of the altered proteins in biofilms formed by Salmonella enterica serovar Enteritidis were downregulated, whereas a much smaller fraction (21%) of proteins were upregulated. Intriguingly, all downregulated proteins were enzymes involved in a wide range of the central metabolic pathways, including translation; amino acid biosynthetic pathways; nucleobase, nucleoside, and nucleotide biosynthetic processes; ATP synthesis-coupled proton transport; the pentose phosphate shunt; and carboxylic acid metabolic processes, indicating that ZnO NPs exert a panmetabolic toxic effect on this prokaryotic organism. In addition to their panmetabolic toxicity, ZnO NPs induced profound changes in cell envelope morphology, imposing additional necrotic effects and triggering the envelope stress response of Salmonella serovar Enteritidis. The envelope stress response effect activated periplasmic chaperones and proteases, transenvelope complexes, and regulators, thereby facilitating protection of this prokaryotic organism against ZnO NPs.
Original language | English (US) |
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Pages (from-to) | 3317-3328 |
Number of pages | 12 |
Journal | Antimicrobial agents and chemotherapy |
Volume | 59 |
Issue number | 6 |
DOIs | |
State | Published - 2015 |
Bibliographical note
Funding Information:For this project has been provided in part through industry councils from Saskatchewan, Ontario, and Quebec, Canada, which deliver the Canadian Agricultural Adaptation Program (CAAP) on behalf of Agriculture and Agri-Food Canada. This study also received strategic funding from Environment Canada (Chemicals Management Plan-Nanotechnology).
Funding Information:
Funding for this project has been provided in part through industry councils from Saskatchewan, Ontario, and Quebec, Canada, which deliver the Canadian Agricultural Adaptation Program (CAAP) on behalf of Agriculture and Agri-Food Canada. This study also received strategic funding from Environment Canada (Chemicals Management Plan—Nanotechnology).
Publisher Copyright:
© Copyright 2015 American Society for Microbiology. All Rights Reserved.