These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Effects of sublethal doses of silver nanoparticles on Bacillus subtilis planktonic and sessile cells.
    Author: Gambino M, Marzano V, Villa F, Vitali A, Vannini C, Landini P, Cappitelli F.
    Journal: J Appl Microbiol; 2015 May; 118(5):1103-15. PubMed ID: 25702880.
    Abstract:
    AIMS: Due to their antimicrobial activity, silver nanoparticles (Ag-NPs) are being increasingly used in a number of industrial products. The accumulation of Ag-NPs in the soil might affect plant growth-promoting rhizobacteria and, in turn, the plants. We describe the effects of Ag-NPs on the soil bacteria Azotobacter vinelandii and Bacillus subtilis. METHODS AND RESULTS: In growth-inhibition studies, A. vinelandii showed extreme sensitivity to Ag-NPs, compared to B. subtilis. We investigated the effects of Ag-NPs at subinhibitory concentrations, both on planktonic and sessile B. subtilis cells. As determined by 2,7-dichlorofluorescein-diacetate assays, Ag-NPs increase the formation of reactive oxygen species in planktonic cells, but not in sessile cells, suggesting the activation of scavenging systems in biofilms. Consistently, proteomic analysis in B. subtilis Ag-NPs-treated biofilms showed increased production of proteins related to quorum sensing and involved in stress responses and redox sensing. Extracellular polysaccharides production and inorganic phosphate solubilization were also increased, possibly as part of a coordinated response to stress. CONCLUSIONS: At low concentrations, Ag-NPs killed A. vinelandii and affected cellular processes in planktonic and sessile B. subtilis cells. SIGNIFICANCE AND IMPACT OF THE STUDY: Re-direction of gene expression, linked to selective toxicity, suggests a strong impact of Ag-NPs on soil bacterial communities.
    [Abstract] [Full Text] [Related] [New Search]