Format

Send to

Choose Destination
J Biomed Mater Res. 2000 Dec 15;52(4):662-8.

A mechanistic study of the antibacterial effect of silver ions on Escherichia coli and Staphylococcus aureus.

Author information

1
Department of Materials Science and Engineering, Tsinghua University, Beijing 100084, China.

Abstract

To investigate the mechanism of inhibition of silver ions on microorganisms, two strains of bacteria, namely Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus), were treated with AgNO(3) and studied using combined electron microscopy and X-ray microanalysis. Similar morphological changes occurred in both E. coli and S. aureus cells after Ag(+) treatment. The cytoplasm membrane detached from the cell wall. A remarkable electron-light region appeared in the center of the cells, which contained condensed deoxyribonucleic acid (DNA) molecules. There are many small electron-dense granules either surrounding the cell wall or depositing inside the cells. The existence of elements of silver and sulfur in the electron-dense granules and cytoplasm detected by X-ray microanalysis suggested the antibacterial mechanism of silver: DNA lost its replication ability and the protein became inactivated after Ag(+) treatment. The slighter morphological changes of S. aureus compared with E. coli recommended a defense system of S. aureus against the inhibitory effects of Ag(+) ions.

PMID:
11033548
[Indexed for MEDLINE]

Supplemental Content

Loading ...
Support Center