Dataset Information

Single-walled carbon nanotubes alter cytochrome c electron transfer and modulate mitochondrial function.

ABSTRACT: Single-walled carbon nanotubes (SWCNTs) are broadly used for various biomedical applications such as drug delivery, in vivo imaging, and cancer photothermal therapy due to their unique physiochemical properties. However, once they enter the cells, the effects of SWCNTs on the intracellular organelles and macromolecules are not comprehensively understood. Cytochrome c (Cyt c), as a key component of the electron transport chain in mitochondria, plays an essential role in cellular energy consumption, growth, and differentiation. In this study, we found the mitochondrial membrane potential and mitochondrial oxygen uptake were greatly decreased in human epithelial KB cells treated with SWCNTs, which accompanies the reduction of Cyt c. SWCNTs deoxidized Cyt c in a pH-dependent manner, as evidenced by the appearance of a 550 nm characteristic absorption peak, the intensity of which increased as the pH increased. Circular dichroism measurement confirmed the pH-dependent conformational change, which facilitated closer association of SWCNTs with the heme pocket of Cyt c and thus expedited the reduction of Cyt c. The electron transfer of Cyt c is also disturbed by SWCNTs, as measured with electron spin resonance spectroscopy. In conclusion, the redox activity of Cyt c was affected by SWCNTs treatment due to attenuated electron transfer and conformational change of Cyt c, which consequently changed mitochondrial respiration of SWCNTs-treated cells. This work is significant to SWCNTs research because it provides a novel understanding of SWCNTs' disruption of mitochondria function and has important implications for biomedical applications of SWCNTs.

SUBMITTER: Ma X

PROVIDER: S-EPMC3548237 | biostudies-literature | 2012 Dec

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Single-walled carbon nanotubes alter cytochrome c electron transfer and modulate mitochondrial function.

Ma Xiaowei X Zhang Li-Hua LH Wang Li-Rong LR Xue Xue X Sun Ji-Hong JH Wu Yan Y Zou Guozhang G Wu Xia X Wang Paul C PC Wamer Wayne G WG Yin Jun-Jie JJ Zheng Kaiyuan K Liang Xing-Jie XJ

ACS nano 20121129 12

Single-walled carbon nanotubes (SWCNTs) are broadly used for various biomedical applications such as drug delivery, in vivo imaging, and cancer photothermal therapy due to their unique physiochemical properties. However, once they enter the cells, the effects of SWCNTs on the intracellular organelles and macromolecules are not comprehensively understood. Cytochrome c (Cyt c), as a key component of the electron transport chain in mitochondria, plays an essential role in cellular energy consumptio ...[more]

PMID: 23171082

Similar Datasets

Project description:Microbial electrochemical systems (MESs) rely on the microbes' ability to transfer charges from their anaerobic respiratory processes to electrodes through extracellular electron transfer (EET). To increase the generally low output signal in devices, advanced bioelectrical interfaces tend to augment this problem by attaching conducting nanoparticles, such as positively charged multiwalled carbon nanotubes (CNTs), to the base carbon electrode to electrostatically attract the negatively charged bacterial cell membrane. On the other hand, some reports point to the importance of the magnitude of the surface charge of functionalized single-walled CNTs (SWCNTs) as well as the size of functional groups for interaction with the cell membrane, rather than their polarity. To shed light on these phenomena, in this study, we prepared and characterized well-solubilized aqueous dispersions of SWCNTs functionalized by either positively or negatively charged cellulose-derivative polymers, as well as with positively charged or neutral small molecular surfactants, and tested the electrochemical performance of Shewanella oneidensis MR-1 in MESs in the presence of these functionalized SWCNTs. By simple injection into the MESs, the positively charged polymeric SWCNTs attached to the base carbon felt (CF) electrode, and as fluorescence microscopy revealed, allowed bacteria to attach to these structures. As a result, EET currents continuously increased over several days of monitoring, without bacterial growth in the electrolyte. Negatively charged polymeric SWCNTs also resulted in continuously increasing EET currents and a large number of bacteria on CF, although SWCNTs did not attach to CF. In contrast, SWCNTs functionalized by small-sized surfactants led to a decrease in both currents and the amount of bacteria in the solution, presumably due to the detachment of surfactants from SWCNTs and their detrimental interaction with cells. We expect our results will help researchers in designing materials for smart bioelectrical interfaces for low-scale microbial energy harvesting, sensing, and energy conversion applications.

Dataset Information

Single-walled carbon nanotubes alter cytochrome c electron transfer and modulate mitochondrial function.

Publications

Single-walled carbon nanotubes alter cytochrome c electron transfer and modulate mitochondrial function.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets