Charge-Associated Effects of Fullerene Derivatives on Microbial Structural Integrity and Central Metabolism

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• 作者：Yinjie J. Tang ; Jared M. Ashcroft ; Ding Chen ; Guangwei Min ; Chul-Hyun Kim ; Bipasha Murkhejee ; Carolyn Larabell ; Jay D. Keasling ; Fanqing Frank Chen
• 刊名：Nano Letters
• 出版年：2007
• 出版时间：March 2007
• 年：2007
• 卷：7
• 期：3
• 页码：754 - 760
• 全文大小：425K
• 年卷期：v.7,no.3(March 2007)
• ISSN：1530-6992

文摘

The effects of four types of fullerene compounds (C₆₀, C₆₀-OH, C₆₀-COOH, C₆₀-NH₂) were examined on two model microorganisms (Escherichiacoli W3110 and Shewanella oneidensis MR-1). Positively charged C₆₀-NH₂ at concentrations as low as 10 mg/L inhibited growth and reducedsubstrate uptake for both microorganisms. Scanning electron microscopy (SEM) revealed damage to cellular structures. Neutrally charged C₆₀and C₆₀-OH had mild negative effects on S. oneidensis MR-1, whereas the negatively charged C₆₀-COOH did not affect either microorganism'sgrowth. The effect of fullerene compounds on global metabolism was further investigated using [3-¹³C]L-lactate isotopic labeling, which tracksperturbations to metabolic reaction rates in bacteria by examining the change in the isotopic labeling pattern in the resulting metabolites(often amino acids).^1-3063020tb00002">063020tb00003"> The ¹³C isotopomer analysis from all fullerene-exposed cultures revealed no significant differences in isotopomerdistributions from unstressed cells. This result indicates that microbial central metabolism is robust to environmental stress inflicted byfullerene nanoparticles. In addition, although C₆₀-NH₂ compounds caused mechanical stress on the cell wall or membrane, both S. oneidensisMR-1 and E. coli W3110 can efficiently alleviate such stress by cell aggregation and precipitation of the toxic nanoparticles. The resultspresented here favor the hypothesis that fullerenes cause more membrane stress^4-6063020tb00005">063020tb00006"> than perturbation to energy metabolism.⁷