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chinese Journal of chemical Physics 2008年第3期21卷 217-220页

作者： Bo Wu Yan-qiu chu Zhao-yun Dai chuan-fan Ding Physical chemistry Institute Department of Chemistry Fudan University Shanghai 200433 China Infectious Disease Department Huadong Hospital Shanghai 200040 China

Allergic contact dermatitis is a delayed hypersensitivity reaction, which results from skin exposure to low molecular weight chemicals such as haptens. To clarify the pathogenic mechanism, electrospray ionization mass spectrometry （ESI-MS） and hydrogen/deuterium （H/D） exchange, as well as UV spectroscopy, were applied to determine the interaction between the model protein cytochrome c （cyt c） and the hapten 2,4- dinitro-fiuorobenzene （DNFB）. The ESI-MS results demonstrate that the conformation of cyt c can change from native folded state into partially unfolded state with the increase of DNFB. The equilibrium state H/D exchange followed by ESI-MS further confirms the above results. UV spectroscopy indicates that the strong- field coordination between iron of heme （prosthetic group） and His18 or Met80 of cyt c is not obviously affected by the hapten.

关键词： Interaction cytochrome c 2 4-dinitro-fluorobenzene ESI-MS

Label-free surface-enhanced infrared spectro-electro-chemical analysis of the Redox potential shift of cytochrome c complexed with a cardiolipin-containing lipid membrane of varied composition

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chinese Physics B 2015年第12期24卷 91-97页

作者：刘丽武烈曾丽姜秀娥 State Key Laboratory of Electroanalytical chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences

In this study, a lipid membrane was fabricated by fusing cardiolipin-phosphatidylcholine（cL_Pc, 1：4） vesicles onto a hydrophobic surface of 1-dodecanethiol（DT） preadsorbed on a nanostructured gold film. By changing the concentration of the DT adsorption solution, we constructed a series of cL Pc-DT bilayers with different hydrophobicity to study the effects of lipid membrane characteristics on the adsorption conformation of cytochrome c（cyt c）. Electrochemical analysis showed that the formal potential is 0.24 V for cyt c-cL_Pc-DT（10）, 0.2 V for cyt c-cL_Pc-DT（20）, and 0.16 V for cyt c-cL_Pc-DT（40） — a gradual positive shift with the decreasing DT concentration — relative to the potential of native cyt c（0.02 V）. Potential-induced surface-enhanced infrared adsorption difference spectroscopy revealed that the gradual positive shift of the formal potential of cL-bound cyt c is determined by the environment with the gradually lowered dielectric constant for the heme cofactor in cL-bound cyt c（Fe^3＋）.

关键词： cytochrome c cardiolipin surface-enhanced infrared adsorption spectroscopy protein-solvent interaction

Humic acid-enhanced electron transfer of in vivo cytochrome c as revealed by electrochemical and spectroscopic approaches

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Journal of Environmental Sciences 2014年第5期26卷 1118-1124页

作者： Jiahuan Tang Yi Liu Yong Yuan Shungui Zhou Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangdong Institute of Eco-environmental and Soil Sciences college of Bioscience and Biotechnology Hunan Agricultural University

Out-membrane cytochrome c （cyt c） plays an important role carrying electrons from the inside of microbes to outside electron acceptors. However, the active sites of cyt c are wrapped by non- conductive peptide chains, hindering direct extracellular electron transfer （EET）. Humic acids （HA） have been previously proven to efficiently facilitate EET. However, the inherent mechanism of HA- stimulated EET has not been well interpreted. Here, to probe the mechanism behind HA-stimulated EET, we studied the interaction between cyt c and HA. The attachment of active in vivo cyt c on a graphite electrode was achieved when MR-1 cells were self-assembled on the electrode surface. Pure horse-heart cyt c was covalently immobilized on an electrode via 4-aminobenzoic acid to create an active in vitro cyt c-enriched surface. cyclic voltammetric measurements and scanning electron microscopy confirmed the immobilization of bacterial cells and pure cyt c protein. Electrochemical methods revealed that HA could enhance the electrocatalytic current of both in vitro and in vivo cyt c towards oxygen and thiosulfate, suggesting enhanced EET. The blue-shifted soret band in the UV-Vis spectra and changes in the excitation/emission matrix fluorescence spectra demonstrated that cyt c interacted with HA to form organic complexes via electrostatic or hydrogen-bonding interactions. The results will help understand electron shuttle-stimulated EET and develop bacteria- based bioremediation and bioenergy technologies.

关键词： cytochrome c humic acid in vivo in vitro extracellular electron transfer

Mechanisms of cytochrome c Extraction by Reverse Micelles

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chemical Research in chinese Universities 2001年第1期17卷 73-76页

作者： YU Yan chun QIAN Bao hua cHU Ying WU Zi sheng GAO chang qing Department of chemical Engineering Huaihai Institute of TechnologyLianyungang 222005P.R.China Department of chemistry Northeast Normal UniversityChangchun 130024P.R.China

The extraction of cytochrome c was carried out by means of phase transfer technique with three different reverse micellar systems, i.e. , a cTAB micellar solution in n butyl alcohol chloroform(volume ratio 4∶1), an AOT micellar solution in isooctane and a SDSS D 2EHPA micellar solution in isooctane. The extraction mechanisms were studied. The results show that the extraction mechanisms for the same proteins with different types of reverse micellar systems can be distinct. The extraction of cytochrome c with cTAB and SDSS D 2EHPA reverse micellar systems are carried out according to the mechanism of electrostatic interaction. However, in the extraction of cytochrome c with the AOT reverse micellar system, the electrostatic interaction between the protein and the surfactant is not important.

关键词： Mechanism cytochrome c Extraction Reverse micelles

QcM and Ec-SPR Studies of cytochrome c Self-assembled on Au Electrode and Enhancement of SPR Signal by Au Nanoparticles

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chemical Research in chinese Universities 2012年第6期28卷 1061-1065页

作者： WANG Yan-yan JIANG Yan-xla ZHOU You-chen LI Yan-yan MA Zhi-fang SUN Shi-gang State Key Laboratory of Physical chemistry of Solid Surfaces Department of ChemistryCollege of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P. R. China

Quartz crystal microbalance（QcM） and cyclic voltammetry（cV） were used to characterize the monolayer of cytochrome c（cyt c）,which was adsorbed on gold film modified with alkanethiol mixed monolayer.A direct comparison of protein surface coverages calculated from QcM and cyclic voltammetric measurements illustrates that the ratio of the electroactive cyt c to the total surface-confined cyt c is 34%,which suggests that the orientation is a main factor affecting the electroactivity of cyt ***,surface plasmon resonance（SPR） measurement combined with cV ＂in situ＂ was used to investigate the conformational change of cyt c in the redox ***,Au nanoparticles（Au NPs） were adsorbed on the surface of cyt *** result indicates that Au NPs promote electron transfer between cyt c and the gold electrode,and SPR result suggests Au NPs enhance SPR signal.

关键词： cytochrome c Gold film Self-assembly Electrochemical-surface plasmon resonance(Ec-SPR)

Electrochemical and Spectroscopic Study on the Interaction of cytochrome c with Anionic Lipid Vesicles

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chinese Journal of chemistry 2003年第5期21卷 544-549页

作者：景卫国刘长伟唐纪琳吴正岩董绍俊汪尔康 State Key Laboratory of Electroanalytical chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 China

The structure and the electron-transfer of cytochrome c binding on the anionic lipid vesicles were analyzed by electrochemical and various spectroscopic methods. It was found that upon binding to anionic lipid membrane, the formal potential of. cytochrome c shifted 30 mV negatively indicating an eager redox interaction than that in its native state. This is due to the local alteration of the coordination and the heme crevice. The structural Perturbation in which a molten globule-like state is formed during binding to anionic lipid vesicles is more important. This study may help to understand the mechanism of the electron-transfer reactions of cytochrome c at the mitochondrial membrane.

关键词： cytochrome c electrochemistry dimyristoylphosphatidylglycerol circular dichroism electrospray ionization mass spectra

Direct Electrochemistry of cytochrome c at a Hierarchically Nanostructured TiO_(2) Quantum Electrode

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Nano Research 2010年第5期3卷 369-378页

作者： Li Liu Ning Wang Xia cao Lin Guo School of chemistry and Environment Beijing University of Aeronautics and AstronauticsBeijing 100191China School of Material Science and Engineering Jiangsu University of Science and TechnologyJiangsu 212003China

Monodisperse TiO2 nanoparticles and urchin-like hierarchical TiO2 nanospheres assembled with ultrathin quantum nanowires(about 2 nm)have been synthesized by a simple template-free wet chemical *** morphology,structure,and crystallinity of the TiO2 nanomaterials were investigated by field emission scanning electron microscopy(FESEM),X-ray diffraction(XRD),and high resolution transmission electron microscopy(HRTEM).Electrochemical measurements with the hierarchically nanostructured TiO2 nanospheres as an electrode showed much better reversibility for direct electrochemistry of cytochrome c(cyt c)and much higher sensitivity than for an electrode composed of the monodisperse TiO2 *** excellent performance of the hierarchical TiO2 nanospheres may result from a quantum size effect,and their favorable nanostructure(with the presence of an abundance of both uniform macropores and mesopores),excellent structural stability and high specific surface *** relative ionic strength had significant effect on the direct *** high ionic strengths relative to cyt c concentration(I/c)induced a conformational change of cyt c on the nanostructure-coated electrode,from the native state to a partially unfolded one in 25 mmol/L phosphate buffer solution(pH 6.8).

关键词： Hierarchically nanostructured TiO2 cytochrome c ionic strength bioelectrochemistry

Electrochemical and spectroelectrochemical characterization of different mesoporous TiO2 film electrodes for the immobilization of cytochrome c

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Frontiers of Materials Science 2018年第1期12卷 64-73页

作者： Stavros KATSIAOUNIS christina TIFLIDIS christina TSEKOURA Emmanuel TOPOGLIDIS Department of Materials Science University of Patras Rion 26504 Greece

In this work three different mesoporous TiO2 film electrodes were prepared and used for the immobilization of cytochrome c （cyt-c）. Films prepared via a standard sol-gel route （SG-films） were compared with commercially available benchmark nanotitania materials, namely P25 Degussa （P25-films） and Dyesol nanopaste （Dyesol films）. Their properties, film deposition characteristics and their abilities to adsorb protein molecules in a stable and functional way were examined. We investigated whether it is possible, rather than preparing TiO2 films using multistep, lengthy and not always reproducible sol-gel procedures, to use commercially available nanotitania materials and produce reproducible films faster that exhibit all the properties that make TiO2 films ideal for protein immobilization. Although these materials are formulated primarily for dye-sensitized solar cell applications, in this study we found out that protein immobilization is facile and remarkably stable on all of them. We also investigated their electrochemical properties by using cyclic voltammetry and spectroelectrochemistry and found out that not only direct reduction of Fe（III）-heme to Fe（II）-heme of immobilized cyt-c was possible on all flms but that the adsorbed protein remained electroactive.

关键词： TiO2 films spectroelectrochemistry cyclic voltammetry cytochrome c

Direct Electrochemistry of cytochrome c on the Glassy carbon Electrode Modified with 1-Pyrenebutyric Acid/MWNTs

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chinese chemical Letters 2005年第9期16卷 1237-1240页

作者： Qiang ZHAO Qian Kun ZHUANG college of chemistry and Molecular Engineering Peking University Beijing 100871

With 1-Pymnebutyric acid （PBA） and multiwalled carbon nanotubes （MWNTs）, glassy carbon electrode modified was successfully prepared. In phosphate buffer solution （pH 7,0）, the direct electrochemistry of cytochrome c （cyt c） was realized. In the cyclic voltammetry experiment two pairs of redox peaks ofcyt c were observed at 0.018 V and -0.314 V （vs. ScE）, respectively. The redox reaction at 0.018 V was diffusion controlled, while the redox reaction at -0.314 V was adsorption controlled.

关键词： cytochrome c carbon nanomhes 1-pyrenebutyric acid modified electrode

Apoptosis of non-tumor cells contributes to increased serum cytochrome c level in a neuroblastoma xenograft model

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chinese Medical Journal 2012年第2期125卷 316-320页

作者： Zhang Da Yu Jie-kai Yang Fu-quan Wang Lei Zhang Guo-feng Meng Qing-lei Mu Xin Ma Wei Jia Zhan-kui Wang Jia-xiang Zhengzhou Univ Affiliated Hosp 1 Dept Pediat Surg Zhengzhou 450052 Henan Peoples R China Zhejiang Univ Coll Med Affiliated Hosp 2 Inst Canc Hangzhou 310009 Zhejiang Peoples R China chinese Acad Sci Inst Biophys Beijing 100101 Peoples R China Zhengzhou childrens Hosp Zhengzhou 450053 Henan Peoples R China

Background Neuroblastoma （NB） is one of the most common malignant solid tumors of *** is still not clear whether the apoptosis of tumor cells or the non-tumor cells contributes to the increase of concentration of cytochrome c （cyt c） in the serum of the cancer *** aim of this research was to identify the source of the cyt c in the serum when the tumor grows up by subcutaneous inoculation of human NB cells into nude *** We subcutaneously inoculated human NB cells （KP-N-NS） into nude mice and collected the sera of tumor-bearing mice （n=14） and control mice （n=25） 4 weeks later in order to screen for and identify differentially expressed proteins in the *** expressed proteins in the serum were screened by surface-enhanced laser desorption/ionization-time-of-fiight （SELDI-TOF） mass *** The relative intensity of a protein having a mass-to-charge ratio （m/z） of 11 609 was 3338.37±3410.85 in the tumor group and 59.84±40.74 in the control group,indicating that the expression level of this protein in the tumor group was 55.8 times higher than that in the control *** proteins were separated and purified by high-performance liquid chromatography （HPLc）.Liquid chromatography coupled with tandem mass spectrometry （Lc-MS/MS） was performed to produce peptide mass fingerprints （PMFs）.Spectrum analysis and a database search revealed that the highly expressed protein （m/z=11605.4） from the serum of tumor-bearing mice was the mouse cyt *** Increased concentration of cyt c in the serum of tumor-bearing nude mice might be partially attributed to the secretion of this protein by non-tumor cells.

关键词： neuroblastoma cytochrome c apoptosis protein array analysis