Proteomic analysis of the mode of antibacterial action of silver nanoparticles

Chun Nam Lok, Chi Ming Ho, Rong Chen, Qing Yu He, Wing Yiu Yu, Hongzhe Sun, Paul Kwong Hang Tam, Jen Fu Chiu, Chi Ming Che

Research output: Journal article publicationJournal articleAcademic researchpeer-review

1108 Citations (Scopus)

Abstract

Silver nanoparticles (nano-Ag) are potent and broad-spectrum antimicrobial agents. In this study, spherical nano-Ag (average diameter = 9.3 nm) particles were synthesized using a borohydride reduction method and the mode of their antibacterial action against E. coli was investigated by proteomic approaches (2-DE and MS identification), conducted in parallel to analyses involving solutions of Ag+ions. The proteomic data revealed that a short exposure of E. coli cells to antibacterial concentrations of nano-Ag resulted in an accumulation of envelope protein precursors, indicative of the dissipation of proton motive force. Consistent with these proteomic findings, nano-Ag were shown to destabilize the outer membrane, collapse the plasma membrane potential and deplete the levels of intracellular ATP. The mode of action of nano-Ag was also found to be similar to that of Ag+ions (e.g., Dibrov, P. et al, Antimicrob. Agents Chemother. 2002, 46, 2668-2670); however, the effective concentrations of nano-Ag and Ag+ions were at nanomolar and micromolar levels, respectively. Nano-Ag appear to be an efficient physicochemical system conferring antimicrobial silver activities.
Original languageEnglish
Pages (from-to)916-924
Number of pages9
JournalJournal of Proteome Research
Volume5
Issue number4
DOIs
Publication statusPublished - 1 Apr 2006
Externally publishedYes

Keywords

  • Antibacterial agents
  • ATP
  • E. coli
  • Membrane potential
  • Outer membrane proteins
  • Silver ions
  • Silver nanoparticles

ASJC Scopus subject areas

  • Biochemistry
  • Chemistry(all)

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