The antimicrobial properties of silver nanoparticles in Bacillus subtilis are mediated by released Ag+ ions
學年 104
學期 1
出版（發表）日期 2015-12-15
作品名稱 The antimicrobial properties of silver nanoparticles in Bacillus subtilis are mediated by released Ag+ ions
作品名稱（其他語言）
著者 Yi-Huang Hsueh; Kuen-Song Lin; Wan-Ju Ke; Chien-Te Hsieh; Chao-Lung Chiang; Dong-Ying Tzou; Shih-Tung Liu
單位
出版者
著錄名稱、卷期、頁數 PloS one 10,(12), p. 1-17
摘要 The superior antimicrobial properties of silver nanoparticles (Ag NPs) are well-documented, but the exact mechanisms underlying Ag-NP microbial toxicity remain the subject of intense debate. Here, we show that Ag-NP concentrations as low as 10 ppm exert significant toxicity against Bacillus subtilis, a beneficial bacterium ubiquitous in the soil. Growth arrest and chromosomal DNA degradation were observed, and flow cytometric quantification of propidium iodide (PI) staining also revealed that Ag-NP concentrations of 25 ppm and above increased membrane permeability. RedoxSensor content analysis and Phag-GFP expression analysis further indicated that reductase activity and cytosolic protein expression decreased in B. subtilis cells treated with 10–50 ppm of Ag NPs. We conducted X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) analyses to directly clarify the valence and fine structure of Ag atoms in B. subtilis cells placed in contact with Ag NPs. The results confirmed the Ag species in Ag NP-treated B. subtilis cells as Ag2O, indicating that Ag-NP toxicity is likely mediated by released Ag+ ions from Ag NPs, which penetrate bacterial cells and are subsequently oxidized intracellularly to Ag2O. These findings provide conclusive evidence for the role of Ag+ ions in Ag-NP microbial toxicity, and suggest that the impact of inappropriately disposed Ag NPs to soil and water ecosystems may warrant further investigation.
關鍵字
語言 en_US
ISSN
期刊性質 國外
收錄於 SCI SSCI Scopus
產學合作
通訊作者 Yi-Huang Hsueh
審稿制度 是
國別 USA
公開徵稿
出版型式 ,電子版
相關連結

機構典藏連結 ( http://tkuir.lib.tku.edu.tw:8080/dspace/handle/987654321/127462 )

SDGS 潔淨水與衛生,產業創新與基礎設施