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THE EFFECT OF HYPOCRELLIN B ON THE FLUORESCENCE OF BACTERIORHODOPSIN
竹红菌乙素对菌紫质荧光的影响

Hu Kunsheng,Le Jiachang,Zhang Hengtao,Wang Aojin,
胡坤生
,乐加昌,张衡涛,王敖金

生物物理学报 , 1996,
Abstract: The interaction between Hypocrellin B and bacteriorhodopsin was studied using fluorescence method. The effect of Hypocrellin B onn absorption spectrum of Bacteriorhodopsin, the concentration and tempererature dependence of Hypocrellin B on the fiuorescence quenching of bacteriorhodopsin showed that Hypocrellin B was a new fluorescence quencher and the intrinsic fluorescence quenching of Bacteriorhodopsin was a dynamic process.The difference of fluorescence quenching between light-adapted and dark-adapted bacteriorhodopsin showed this quencher can be used in the study of conformational change of Biomembrane proteins.
Abnormal behavior of fluorescence quenching of gramicidin A in phase transition of lipid vesicles by hypocrellin B—Does an electron transfer inverted region exist?
Jiachang Yue,Yeping Li,Yaxian Su,Kechun Lin
Chinese Science Bulletin , 1999, DOI: 10.1007/BF02887123
Abstract: The fluorescence of gramicidin A(GA) in lipid bilayer may be quenched by Hypocrellin B. When the phospholipids undergo a phase transition from gel to liquid crystalline phase, the reaction rate decreases unusually. This phenomenon has been analyzed by Marcus’ photoinduced electron theory, and an electron transfer inverted region hypothesis is proposed, which may adequately explain this abnormal phenomenon.
THE STUDIES ON THE RED BLOOD CELL MEMBRANE AFFECTED BY MERCURIDES
汞化合物对红细胞膜作用的研究

程极济,周培林,陈水月
生物物理学报 , 1986,
Abstract: This paper reports the effects of mercurides on the red blood cell membrane including the changes of fluorescence and phosphorescence spectra of membrane protein; the fluorescence polarization of DPH labelled on membrane; the bindings of membrane with ANS and their relationships with the hemolysis of RBC affected by mercurides.The intensity of fluorescence of the membrane protein decreased with the increase of the concentration of mercurides. The quenching effect of the mercurides in 5p7.5 buffer solution is HgCl2> Hg(AC)2 PCMB. The quenching effect is two phases process in both 5p7.5 and PBS buffer solutions, but the slow phase of the quenching curve in PBS buffer solution changes very little. The fluorescence quenching effect of mercurides is due to the formation of non-fluorescent complex of R-Trp-Hg+ and the energy transfer from the Trp to the complex of R-S-Hg+. The intensity of phosphorescence of the membrane protein also decreased with the increase of the concentrtaion of HgCl2, but the ratio of P/F increased. As the concentration of HgCl2 and PCMB increase, the fluorescence polarization of DPH labelled on the ghost increased. The increase of polarization means the decrease of membrane fluidity which it may cause the hemolysis of the red blood cells. The dindings of ANS on the ghost protein increased with increase of mercurides, this result also coincides with the hemolvsis of RBC.
Fluorescence Correlation Spectroscopy Measurements of the Membrane Protein TetA in Escherichia coli Suggest Rapid Diffusion at Short Length Scales  [PDF]
David Chow, Lin Guo, Feng Gai, Mark Goulian
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0048600
Abstract: Structural inhomogeneities in biomembranes can lead to complex diffusive behavior of membrane proteins that depend on the length or time scales that are probed. This effect is well studied in eukaryotic cells, but has been explored only recently in bacteria. Here we used fluorescence recovery after photobleaching (FRAP) and fluorescence correlation spectroscopy (FCS) to study diffusion of the membrane protein TetA-YFP in E. coli. We find that the diffusion constant determined from FRAP is comparable to other reports of inner membrane protein diffusion constants in E. coli. However, FCS, which probes diffusion on shorter length scales, gives a value that is almost two orders of magnitude higher and is comparable to lipid diffusion constants. These results suggest there is a population of TetA-YFP molecules in the membrane that move rapidly over short length scales (~ 400 nm) but move significantly more slowly over the longer length scales probed by FRAP.
Membrane bound protein diffusion viewed by fluorescence recovery after bleaching experiments : models analysis  [PDF]
C. Favard,N. Olivi-Tran,J. -L. Meunier
Physics , 2002,
Abstract: Diffusion processes in biological membranes are of interest to understand the macromolecular organisation and function of several molecules. Fluorescence Recovery After Photobleaching (FRAP) has been widely used as a method to analyse this processes using classical Brownian diffusion model. In the first part of this work, the analytical expression of the fluorescence recovery as a function of time has been established for anomalous diffusion due to long waiting times. Then, experimental fluorescence recoveries recorded in living cells on a membrane-bound protein have been analysed using three different models : normal Brownian diffusion, Brownian diffusion with an immobile fraction and anomalous diffusion due to long waiting times.
Homodimerization of Amyloid Precursor Protein at the Plasma Membrane: A homoFRET Study by Time-Resolved Fluorescence Anisotropy Imaging  [PDF]
Viviane Devauges, Catherine Marquer, Sandrine Lécart, Jack-Christophe Cossec, Marie-Claude Potier, Emmanuel Fort, Klaus Suhling, Sandrine Lévêque-Fort
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0044434
Abstract: Classical FRET (F?rster Resonance Energy Transfer) using two fluorescent labels (one for the donor and another one for the acceptor) is not efficient for studying the homodimerization of a protein as only half of the homodimers formed can be identified by this technique. We thus resorted to homoFRET detected by time-resolved Fluorescence Anisotropy IMaging (tr-FAIM). To specifically image the plasma membrane of living cells, an original combination of tr-FAIM and Total Internal Reflection Fluorescence Lifetime Imaging Microscope (TIRFLIM) was implemented. The correcting factor accounting for the depolarization due to the high numerical aperture (NA) objective, mandatory for TIRF microscopy, was quantified on fluorescein solutions and on HEK293 cells expressing enhanced Green Fluorescence Protein (eGFP). Homodimerization of Amyloid Precursor Protein (APP), a key mechanism in the etiology of Alzheimer’s disease, was measured on this original set-up. We showed, both in epifluorescence and under TIRF excitation, different energy transfer rates associated with the homodimerization of wild type APP-eGFP or of a mutated APP-eGFP, which forms constitutive dimers. This original set-up thus offers promising prospects for future studies of protein homodimerization in living cells in control and pathological conditions.
A FLUORESCENCE PHOTOBLEACHING RECOVERY STUDY OF HYPOCRELLIN B ON THE LATERAL DIFFUSION OF ASCITIC HEPATOMA CELL MEMBRANE
用荧光漂白恢复技术研究竹红菌乙素在小鼠肝癌细胞内的扩散过程

Yue Jiachang Wang Wenyu Jiang Pidong Fu Shimi Pang Suzhen,
乐加昌
,王文玉,江丕栋,傅世密,庞素珍

生物物理学报 , 1993,
Abstract: The fluorescence photobleaching recovery technique was used to examine the effect of HB on the lateral diffusion and fluorescence recovery rate in the Ascitic Hepatoma(AH) cell membrane and solutions. The results showed that the lateral diffusion D HB in membrane is 3.2× 10-9cm2s-1 and fluorescence recovery rate is near 97.8%; The experiments illustrated that in AH cell membrane HB is in free state.
Characterization of the latent membrane protein 1 signaling complex of Epstein-Barr virus in the membrane of mammalian cells with bimolecular fluorescence complementation
Pooja Talaty, Amanda Emery, David N Everly
Virology Journal , 2011, DOI: 10.1186/1743-422x-8-414
Abstract: LMP1-TRAF and LMP1-LMP1 interactions were assayed by BiFC using fluorescence microscopy and flow cytometry. Function of LMP1 BiFC contructs were confirmed by transformation assays and nuclear factor- κB (NF-κB) reporter assays.BiFC was observed between LMP1 and TRAF2 or TRAF3 and mutation of the LMP1 signaling domains reduced complementation. Fluorescence was observed in previously described LMP1 signaling locations. Oligomerization of LMP1 with itself induced complementation and BiFC. LMP1-BiFC constructs were fully functional in rodent fibroblast transformation assays and activation of NF-κB reporter activity. The BiFC domain partially suppressed some LMP1 mutant phenotypes.Together these data suggest that BiFC is a unique and novel platform to identify and characterize proteins recruited to the LMP1-signaling complex.Epstein-Barr virus (EBV) is a DNA tumor virus that latently infects and immortalizes B-lymphocytes. The latent membrane proteins of EBV induce constitutive signaling to establish latency and ensure the survival of the infected cell [1,2]. Latent membrane protein 1 (LMP1) of EBV is termed the EBV oncogene as it is required for EBV B-cell transformation and sufficient to transform rodent fibroblasts [3-9]. LMP1 expression is also frequently detected in the cancers associated with EBV [1,2,10-12]. It alters the cellular environment by inducing a number of signaling pathways, including nuclear factor- κ B (NF-κB), phosphoinositide 3-kinase (PI3K), mitogen-activated protein kinase, and c-Jun N-terminal kinase [6,7,13-19].LMP1 has a short cytoplasmic amino terminus, a six pass transmembrane domain, and a cytoplasmic carboxyl-terminal signaling domain. The transmembrane domain is required for ligand-independent self-association and localization to lipid raft domains of the membrane [20-26]. Mutations in the membrane domain that impair LMP1 raft localization can block signaling [22,27-29]. LMP1 signaling is initiated by binding of adaptor proteins to the two
Raman spectroscopic study of space structure of membrane proteins and membrane lipids in photodamaged human erythrocyte sensitized by hypocrellin B
Yiming Xu,Hongying Yang,Zhiyi Zhang
Science China Life Sciences , 1998, DOI: 10.1007/BF02882902
Abstract: Laser Raman spectroscopy was used to investigate the photodamage characteristics of human erythrocyte membranes sensitized by hypocrellin B (HB) at the molecular level. It brought to light that the essence of the changes of erythrocyte membranes’ functions caused by membrane protein cross-linking and membrane lipid peroxidation, including increase of fluidity and ion permeability of membranes, etc., was that the orderly structure of erythrocyte membranes had been damaged by the active oxygen (1O2, O2 and, OH) generated by HB, including the decrease of α-helix, β-sheet and the increase of random coil in the main-chain of membrane proteins, the decrease of mercapto groups, indole rings, p-hydroxy phenyl rings, monosubstituted phenyl rings, etc. in the side-chain, and the changes of the conformations of membrane lipids as well. With the increase of the irradiation time, thetrans conformation of membrane lipids increased first, then decreased. On the contrary, thegauche conformation decreased first, then increased. In addition, the decrease of the intensities of the lines assigned to bending vibration of the conformation-insensitive CH2 and CH3 of membrane proteins and lipids suggested that break of their chains had occurred.
Raman spectroscopic study of space structure of membrane proteins and membrane lipids in photodamaged human erythrocyte sensitized by hypocrellin B

XU Yiming,YANG Hongying,ZHANG Zhiyi,

中国科学C辑(英文版) , 1998,
Abstract: Laser Raman spectroscopy was used to investigate the photodamage characteristics of human erythrocyte membranes sensitized by hypocrellin B (HB) at the molecular level. It brought to light that the essence of the changes of erythrocyte membranes’ functions caused by membrane protein cross-linking and membrane lipid peroxidation, including increase of fluidity and ion permeability of membranes, etc., was that the orderly structure of erythrocyte membranes had been damaged by the active oxygen (1O2, O2 and, OH) generated by HB, including the decrease of α-helix, β-sheet and the increase of random coil in the main-chain of membrane proteins, the decrease of mercapto groups, indole rings, p-hydroxy phenyl rings, monosubstituted phenyl rings, etc. in the side-chain, and the changes of the conformations of membrane lipids as well. With the increase of the irradiation time, thetrans conformation of membrane lipids increased first, then decreased. On the contrary, thegauche conformation decreased first, then increased. In addition, the decrease of the intensities of the lines assigned to bending vibration of the conformation-insensitive CH2 and CH3 of membrane proteins and lipids suggested that break of their chains had occurred. Project supported by the National Natural Science Foundation of China (Grant No. 39570189).
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