N-terminal hydrophobic residues of the G-protein ADP-ribosylation factor-1 insert into membrane phospholipids upon GDP to GTP exchange.
AuthorsAntonny B,Beraud-Dufour S,Chardin P,Chabre M
JournalBiochemistry
PubMed ID9109679
Shape and lipid-binding site of the nonspecific lipid-transfer protein (sterol carrier protein 2): a steady-state and time-resolved fluorescence study.
'The nonspecific lipid-transfer protein (nsL-TP) from bovine liver was studied with time-resolved and steady-state fluorescence techniques. From the decay of the intrinsic tryptophanyl fluorescence, it was estimated that the rotational correlation time of nsL-TP is 15 ns. This parameter increased only slightly upon addition of an excess of negatively charged ... More
Detection of membrane packing defects by time-resolved fluorescence depolarization.
AuthorsChen SY, Cheng KH
JournalBiophys J
PubMed ID8842226
'Packing defects in lipid bilayer play a significant role in the biological activities of cell membranes. Time-resolved fluorescence depolarization has been used to detect and characterize the onset of packing defects in binary mixtures of dilinoleoylphosphatidylethanolamine/1-palmitoyl-2- oleoylphosphatidylcholine (PE/PC). These PE/PC mixtures exhibit mesoscopic packing defect state (D), as well as ... More
Effect of n-alkanols on lipid bilayer hydration.
AuthorsHo C, Stubbs CD
JournalBiochemistry
PubMed ID9271493
'The effect of a homologous series of aliphatic n-alkanols on the presence of water within the head group and acyl chain region of lipid bilayers was investigated using time-resolved fluorescence spectroscopy according to a previously published approach [Ho, C., Slater, S. J., & Stubbs, C. D. (1995) Biochemistry 34, 6188-6195]. ... More
Influence of the length of the spacer on the partitioning properties of amphiphilic fluorescent membrane probes.
AuthorsBeck A, Heissler D, Duportail G
JournalChem Phys Lipids
PubMed ID8118914
'Four fluorescent diphenylhexatriene derivatives were considered as membrane probes, namely two ammonium compounds, 3-(diphenylhexatrienyl)propyltrimethylammonium (TMAP-DPH) and 22-(diphenylhexatrienyl)docosyltrimethylammonium (LcTMA-DPH), and two phospholipids, 1-palmitoyl-2-[3-(diphenylhexatrienyl)propanoyl]-sn-glyc ero-3-phosphocholine (DPHpPC) and 1-palmitoyl-2-[21-(diphenylhexatrienyl)henicosanoyl]-sn-phos phocholine (LcDPHpPC). For each pair, the molecules differ by the length of the polymethylenic spacer between the fluorescent moiety and the polar head, so ... More
Lateral distribution of cholesterol in dioleoylphosphatidylcholine lipid bilayers: cholesterol-phospholipid interactions at high cholesterol limit.
AuthorsParker A, Miles K, Cheng KH, Huang J
JournalBiophys J
PubMed ID14990480
'Lateral organization of cholesterol in dioleoyl-phosphatidylcholine (DOPC) lipid bilayers at high cholesterol concentration (>45 mol%) was investigated using steady-state fluorescence anisotropy and fluorescent resonance energy transfer techniques. The recently devised Low Temperature Trap method was used to prepare compositionally uniform cholesterol/DOPC liposomes to avoid the problem of lipid demixing. The ... More
Osmotic and curvature stress affect PEG-induced fusion of lipid vesicles but not mixing of their lipids.
AuthorsMalinin VS, Frederik P, Lentz BR
JournalBiophys J
PubMed ID11916865
'Poly (ethylene glycol) (PEG) in the external environment of membrane vesicles creates osmotic imbalance that leads to mechanical stress in membranes and may induce local membrane curvature. To determine the relative importance of membrane stress and curvature in promoting fusion, we monitored contents mixing (CM) and lipid mixing (LM) between ... More
Location of diphenylhexatriene (DPH) and its derivatives within membranes: comparison of different fluorescence quenching analyses of membrane depth.
AuthorsKaiser RD, London E
JournalBiochemistry
PubMed ID9609714
'The average membrane location of a series of diphenylhexatriene (DPH)-derived membrane probes was analyzed by measuring the quenching of DPH fluorescence with a series of nitroxide-labeled lipids in which the depth of the nitroxide group is varied. All DPH derivatives were located deeply within the bilayer. Some derivatives were anchored ... More
Advantages and limitations of 1-palmitoyl-2-[[2-[4- (6-phenyl-trans-1,3,5-hexatrienyl)phenyl]ethyl]carbonyl]-3- sn-phosphatidylcholine as a fluorescent membrane probe.
AuthorsParente RA, Lentz BR
JournalBiochemistry
PubMed ID4084512
'We have investigated the behavior of 1-palmitoyl-2-[[2-[4- (6-phenyl-trans-1,3,5-hexatrienyl)phenyl]ethyl]carbonyl]-3-sn -phosphatidylcholine (DPHpPC) in synthetic, multilamellar phosphatidylcholine vesicles. This fluorescent phospholipid has photophysical properties similar to its parent fluorophore, diphenylhexatriene (DPH). DPHpPC preferentially partitioned into fluid phase lipid (Kf/s = 3.3) and reported a lower phase transition temperature as detected by fluorescence anisotropy ... More
Polymer-induced membrane fusion: potential mechanism and relation to cell fusion events.
AuthorsLentz BR
JournalChem Phys Lipids
PubMed ID8001186
'Poly(ethylene glycol) (PEG) is used widely to mediate cell-cell fusion in the production of somatic cell hybrids and in the fusion injection of macromolecules into cultured cells from erythrocytes or liposomes. However, little is known about the mechanisms by which PEG induces fusion of cell membranes, making its use much ... More
A photophysical model for diphenylhexatriene fluorescence decay in solvents and in phospholipid vesicles.
AuthorsParasassi T, De Stasio G, Rusch RM, Gratton E
JournalBiophys J
PubMed ID2009361
'The fluorescence decay of 1,6-diphenyl-1,3,5-hexatriene (DPH) in pure solvents and in phospholipid vesicles has been measured using frequency domain fluorometry. Data analysis uses a model with two energetically close excited states. The model explains the high quantum yield and the double exponential decay of DPH observed in some pure solvents ... More
Thermodynamics of the membrane insertion process of the M13 procoat protein, a lipid bilayer traversing protein containing a leader sequence.
AuthorsSoekarjo M, Eisenhawer M, Kuhn A, Vogel H
JournalBiochemistry
PubMed ID8573578
'For the first time, the standard free energy change, delta Gzero, of a membrane-inserting protein with a leader sequence has been determined experimentally, using M13 procoat protein as an example. The partition coefficient for the distribution of the procoat protein between the aqueous phase and the membrane phase of preformed ... More
Effects of alcohols on fluorescence anisotropies of diphenylhexatriene and its derivatives in bovine blood platelets: relationships of the depth-dependent change in membrane fluidity by alcohols with their effects on platelet aggregation and adenylate cyclase activity.
AuthorsKitagawa S, Hirata H
JournalBiochim Biophys Acta
PubMed ID1329963
'The effects of three short-chain alkyl alcohols and benzyl alcohol on the membrane fluidity of bovine blood platelets were investigated by studies on the fluorescence anisotropies of diphenylhexatriene (DPH), its cationic trimethylammonium derivative (TMA-DPH) and its anionic propionic acid derivative (DPH-PA). These alcohols decreased the fluorescence anisotropy of DPH, which ... More
Poly(ethylene glycol)-induced lipid mixing but not fusion between synthetic phosphatidylcholine large unilamellar vesicles.
'We have examined the effect of poly(ethylene glycol) (PEG) on stable large unilamellar vesicles formed by a rapid extrusion technique and composed of pure synthetic phosphatidylcholines. The lipid systems studied were the saturated 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and the monounsaturated 1,2-dioleoyl-sn-glycerol-3-phosphocholine (DOPC). PEG at all concentrations (3.8-40 wt %) induced lipid mixing ... More
Fluorescence lifetime distributions of diphenylhexatriene-labeled phosphatidylcholine as a tool for the study of phospholipid-cholesterol interactions.
AuthorsKalb E, Paltauf F, Hermetter A
JournalBiophys J
PubMed ID2611334
'Fluorescence lifetimes of 1-palmitoyl-2-diphenylhexatrienylpro-pionyl-phosphatidylc hol ine in vesicles of palmitoyloleoyl phosphatidylcholine (POPC) (1:300, mol/mol) in the liquid crystalline state were determined by multifrequency phase fluorometry. On the basis of statistic criteria (chi 2red) the measured phase angles and demodulation factors were equally well fitted to unimodal Lorentzian, Gaussian, or uniform ... More
Partitioning of fluorescent phospholipid probes between different bilayer environments. Estimation of the free energy of interlipid hydrogen bonding.
AuthorsShin TB, Leventis R, Silvius JR
JournalBiochemistry
PubMed ID1854750
'Fluorescence spectroscopy has been used to monitor the partitioning of a series of exchangeable neutral phospholipid probes, labeled with carbazole, indolyl or diphenylhexatrienyl moieties, between large unilamellar vesicles containing 1-palmitoyl-2-oleoylphosphatidylcholine (POPC), 1,2-dioleoyloxy-3-(trimethylammonio) propane (DOTAP) or N-hexadecyl-N-(9-octadecenyl)-N,N-dimethylammonium chloride (HODMA). Phosphatidylethanolamine (PE) probes desorb from POPC-containing vesicles at markedly slower rates than ... More
Increasing surface charge density induces interdigitation in vesicles of cationic amphiphile and phosphatidylcholine.
AuthorsRyhänen SJ, Alakoskela JM, Kinnunen PK
JournalLangmuir
PubMed ID15952813
'Binary vesicles of cationic lipid dihexadecyldimethylammoniumbromide (DHAB) and 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) were examined by differential scanning calorimetry, fluorescence spectroscopy, and Fourier transform infrared spectroscopy. DHAB/DMPC vesicles demonstrate a complex dependence of the main-transition temperature (T(m)) on their mole proportion of DHAB, with a maximum of 42 degrees C at X(DHAB) = ... More
Membrane structural dynamics of plasma membranes of living human prostatic carcinoma cells differing in metastatic potential.
AuthorsCalderon RO, Grogan WM, Collins JM
JournalExp Cell Res
PubMed ID1893934
'Rigidity of the outer hemileaflet of the plasma membrane of two prostatic carcinoma cell lines with different metastatic potential, 1-LN and 1-LN-EMS-10, was assessed by steady-state anisotropy, using a battery of fluorescent probes. The "bulk" membrane rigidity sensed by diphenylhexatriene, trimethylammonio-DPH, 1-palmitoyl-2-[DPH-ethylcarbonyl]-phosphatidylcholine, and 10-pyrenedecanoic acid indicated slightly higher rigidity in ... More
Oxidation of unsaturated phospholipids in membrane bilayer mixtures is accompanied by membrane fluidity changes.
AuthorsBorst JW, Visser NV, Kouptsova O, Visser AJ
JournalBiochim Biophys Acta
PubMed ID10962288
'Steady-state and time-resolved fluorescence spectroscopy has been used to obtain information on oxidation processes and associated dynamical and structural changes in model membrane bilayers made from single unilamellar vesicles (SUV''s) of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) mixed with increasing amounts of 1-stearoyl-2-arachidonoyl-sn-glycero-3-phosphocholine (SAPC). The highly unsaturated arachidonoyl chain containing four double bonds is ... More
Fluorescence depolarization study of lamellar liquid crystalline to inverted cylindrical micellar phase transition of phosphatidylethanolamine.
AuthorsCheng KH
JournalBiophys J
PubMed ID2765643
'The orientational order and rotational dynamics of 2-[3-(diphenyl-hexatrienyl) propanoyl]-3-palmitoyl-L-alpha- phosphatidylcholine (DPH-PC) embedded in dioleoylphosphatidyl-ethanolamine (DOPE) were studied by fluorescence depolarization technique. Upon increasing the temperature, the calculated wobbling diffusion constant D perpendicular of the fluorescent probe was found to decrease at the lamellar (L alpha) to inverted cylindrical (H II) ... More
Evolution of lipidic structures during model membrane fusion and the relation of this process to cell membrane fusion.
AuthorsLee J, Lentz BR
JournalBiochemistry
PubMed ID9174340
'The sequence of events involved in poly(ethylene glycol)-mediated fusion of small unilamellar vesicles (SUVs) has been studied. Fusion events were monitored using light scattering for vesicle aggregation, the fluorescence lifetime of membrane probe lipids (DPHpPC and NBD-PS) for membrane mixing, the aqueous fluorescent marker (Tb3+/DPA and H+/HPTS) for contents mixing; ... More
Evaluation of membrane phase behavior as a tool to detect extrinsic protein-induced domain formation: binding of prothrombin to phosphatidylserine/phosphatidylcholine vesicles.
AuthorsTendian SW, Lentz BR
JournalBiochemistry
PubMed ID2397210
'The temperature-composition phase diagram of mixed dimyristoylphosphatidylserine (DMPS) and dimyristoylphosphatidylcholine (DMPC) small unilamellar vesicles was determined in the presence and absence of bound bovine prothrombin by monitoring the phospholipid order-disorder phase separation using diphenylhexatriene (DPH) fluorescence anisotropy. The shape of the membrane temperature-composition diagram was essentially unaltered by the binding ... More
Effects of cholesterol in chylomicron remnant models of lipid emulsions on apoE-mediated uptake and cytotoxicity of macrophages.
AuthorsSakurai A, Morita SY, Wakita K, Deharu Y, Nakano M, Handa T
JournalJ Lipid Res
PubMed ID15930510
'Chylomicron remnants have been suggested to be involved in the development of atherosclerosis. To investigate the mechanisms of chylomicron remnant-induced atherosclerosis, we prepared cholesterol (Chol)-containing emulsion particles as models for chylomicron remnants. Chol markedly increased the apolipoprotein E (apoE) binding maximum of emulsions without changing the binding affinity and thereby ... More
Reorientational properties of fluorescent analogues of the protein kinase C cofactors diacylglycerol and phorbol ester.
AuthorsPap EH, Ketelaars M, Borst JW, van Hoek A, Visser AJ
JournalBiophys Chem
PubMed ID8820410
'The reorientational properties of the fluorescently labelled protein kinase C (PKC) cofactors diacylglycerol (DG) and phorbol ester (PMA) in vesicles and mixed micelles have been investigated using time-resolved polarised fluorescence. The sn-2 acyl chain of DG was replaced by diphenylhexatriene- (DPH) propionic acid, while a dansyl labelled analogue of phorbol ... More
A new fluorescence method for the continuous determination of surface lipid oxidation in lipoproteins and plasma.
AuthorsHofer G, Lichtenberg D, Hermetter A
JournalFree Radic Res
PubMed ID7493038
'We report on a new method for the determination of lipid oxidation in lipoproteins and plasma. The biological lipid system is preloaded with a fluorescent analog of phosphatidylcholine containing diphenylhexatriene (DPH) propionic acid covalently linked to the sn-2 position. When externally added, the respective phospholipid label (DPHPC) localizes to the ... More
Fluorescence analysis of lipoprotein peroxidation.
AuthorsDousset N, Ferretti G, Taus M, Valdiguiè P, Curatola G
JournalMethods Enzymol
PubMed ID8015481
Dynamic fluorescence measurements on the main phase transition of dipalmytoylphosphatidylcholine vesicles.
AuthorsGenz A, Holzwarth JF
JournalEur Biophys J
PubMed ID3757928
The kinetics of the main phase transition in dipalmytoylphosphatidylcholine (DPPC) vesicles have been investigated using our iodine laser-T-jump technique with fluorescence detection. A set of three fluorescent probes has been used to sense different parts of the bilayer hydrocarbon chain region. The well established membrane probes DPH and TMADPH as ... More
The use of a phospholipid analogue of diphenyl-1,3,5-hexatriene to study melittin-induced fusion of small unilamellar phospholipid vesicles.
AuthorsMorgan CG, Thomas EW, Moras TS, Yianni YP
JournalBiochim Biophys Acta
PubMed ID7171592
A phospholipid analogue incorporating the diphenyl-1,3,5-hexatriene (DPH) chromophore has been synthesized. The compound has been shown to have similar fluorescence properties to DPH itself but, unlike DPH, is unable to exchange freely through solution when incorporated as probe in a subset of phospholipid vesicles of given composition. The non-exchangeability of ... More
Inequivalence of fluorescent choline and ethanolamine phospholipids in the erythrocyte membrane: fluorescence lifetime determination in the frequency and time domain.
AuthorsPrenner E, Sommer A, Kungl A, Stütz H, Friedl H, Hermetter A
JournalArch Biochem Biophys
PubMed ID8373186
The fluorescence decay of 1-palmitoyl-2-diphenyl-hexatrienyl-propionyl-sn-glycero-3-phosphocholine and the respective ethanolamine derivative were determined in human erythrocyte ghost membranes by phase and modulation fluorometry. The obtained bimodal distribution decay model could independently be confirmed by pulse fluorometry and data analysis by the exponential series method. Distributional widths of labeled choline and ethanolamine ... More
Influence of the clathrin coat on the membrane lipidic organization of endocytic vesicles: a fluorescence study.
AuthorsLiaubet A, Egret-Charlier M, Kuhry JG
JournalBiochim Biophys Acta
PubMed ID7918559
Endocytic coated vesicles (CV) were purified from bovine brain, and uncoated vesicles (UV) were obtained from the latter by dialysis against 1 M Tris. Membrane dynamics were explored in both vesicle populations using two complementary fluorescence approaches: diphenylhexatriene fluorescence anisotropy to account for rotational lipid movements, and pyrene excimerization with ... More
Specific RNA binding to ordered phospholipid bilayers.
AuthorsJanas T, Janas T, Yarus M,
JournalNucleic Acids Res
PubMed ID16641318
We have studied RNA binding to vesicles bounded by ordered and disordered phospholipid membranes. A positive correlation exists between bilayer order and RNA affinity. In particular, structure-dependent RNA binding appears for rafted (liquid-ordered) domains in sphingomyelin-cholesterol-1,2-dioleoyl-sn-glycero-3-phosphocholine vesicles. Binding to more highly ordered gel phase membranes is stronger, but much less ... More
The interpretation of the time-resolved fluorescence anisotropy of diphenylhexatriene-phosphatidylcholine using the compound motion model.
AuthorsMuller JM, van Faassen EE, van Ginkel G
JournalBiochem Biophys Res Commun
PubMed ID8003006
Time-resolved fluorescence anisotropy experiments on lipid membranes can provide estimates of the molecular order and motion on microscopic scales. For the analysis of anisotropy data the so-called compound motion model was recently introduced to overcome problems with conventional models. We show that this novel model gives good fits for the ... More
The Fluorosome technique for investigating membrane on- and off-loading of drugs by beta-CD and sonicated SUV.
AuthorsFix M, Melchior DL
JournalFEBS Lett
PubMed ID11959114
The application of the Fluorosome technique to test drug delivery systems is described. Fluorosomes, egg phosphatidylcholine liposomes with bilayer embedded fluorophores, were employed to investigate the ability of sonicated small unilamellar vesicles (sSUV) and beta-cyclodextrins (beta-CD) to deliver drugs into or extract drugs from the fluorosome's phospholipid bilayer. The addition ... More
Does ciprofloxacin interact with neutral bilayers? An aspect related to its antimicrobial activity.
AuthorsHernández-Borrell J, Montero MT
JournalInt J Pharm
PubMed ID12550790
Ciprofloxacin (CPX) physicochemical properties, mainly hydrophobicity and microspeciation, appear to be related with the ability of this drug to adsorb and diffuse through lipid environments. We have combined the information from fluorescence anisotropy, quenching and epifluorescence of phospholipid monolayers, to explore effects of CPX at the phospholipid-buffer interface. Two fluorescent ... More
Individual leaflets of a membrane bilayer can independently regulate permeability.
AuthorsNegrete HO, Rivers RL, Goughs AH, Colombini M, Zeidel ML
JournalJ Biol Chem
PubMed ID8662821
Water rapidly crosses most membranes, but only slowly crosses apical membranes of barrier epithelia such as bladder and kidney collecting duct, a feature essential to barrier function. How apical membrane structure reduces permeabilities remains unclear. Cell plasma membranes contain two leaflets of distinct lipid composition; the role of this bilayer ... More
Interaction of ethylazinphos with the physical organization of model and native membranes.
AuthorsVideira RA, Antunes-Madeira Mdo C, Madeira VM
JournalBiochim Biophys Acta
PubMed ID8652607
The interaction of ethylazinphos with the physical organization of model and native membranes was investigated by means of fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (DPH) and of its propionic acid derivative (DPH-PA). Ethylazinphos shifts the phase transition midpoint to lower temperature values and broadens the phase transition profile of bilayers reconstituted with ... More
High-throughput fluorescence screening of antioxidative capacity in human serum.
AuthorsMayer B, Schumacher M, Brandstätter H, Wagner FS, Hermetter A
JournalAnal Biochem
PubMed ID11673881
Diphenylhexatriene-labeled phosphatidylcholine and propionic acid have been established as selective fluorescence markers for the continuous determination of oxidation processes in the lipid and aqueous phases of unfractionated human serum. Oxidation of the respective fluorophores leads to a decrease in fluorescence intensity from which the time-dependent degradation of the marker molecule ... More
The dynamics of lipid motion in sarcoplasmic reticulum membranes determined by steady-state and time-resolved fluorescence measurements on 1,6-diphenyl-1,3,5-hexatriene and related molecules.
AuthorsStubbs CD, Kinosita K, Munkonge F, Quinn PJ, Ikegami A
JournalBiochim Biophys Acta
PubMed ID6466678
Steady-state and time-resolved fluorescence anisotropy measurements were made on 1,6-diphenyl-1,3,5-hexatriene (DPH), 1-(4-trimethylammoniumphenyl)-6-phenyl-1,3,5-hexatriene (TMA-DPH) and 1-acyl-2-(DPH)-phosphatidylcholine (DPH-PC) incorporated into sarcoplasmic reticulum membranes. The results were analysed in terms of the 'wobbling-in-cone' model. Considerable differences in the fluorescence parameters were found. In particular TMA-DPH and DPH-PC showed a smaller cone angle, relating ... More
Membrane-catalyzed nucleotide exchange on DnaA. Effect of surface molecular crowding.
AuthorsAranovich A, Gdalevsky GY, Cohen-Luria R, Fishov I, Parola AH
JournalJ Biol Chem
PubMed ID16517983
DnaA is the initiator protein for chromosomal replication in bacteria; its activity plays a central role in the timing of the primary initiations within the Escherichia coli cell cycle. A controlled, reversible conversion between the active ATP-DnaA and the inactive ADP forms modulates this activity. In a DNA-dependent manner, bound ... More
Fluorescence-quenching study of percolation and compartmentalization in two-phase lipid bilayers.
AuthorsPiknová B, Marsh D, Thompson TE
JournalBiophys J
PubMed ID8842228
Fluorescence quenching of a lipid-labeled fluorophore by a lipid spin-labeled quencher has been studied experimentally in two-component, two-phase phosphatidylcholine bilayers to examine the effect of phase connection and disconnection on quenching. Both fluorophore and quencher prefer the fluid phase. At the percolation threshold, the point at which the fluid phase ... More
Studies of the ethanol-induced interdigitated gel phase in phosphatidylcholines using the fluorophore 1,6-diphenyl-1,3,5-hexatriene.
AuthorsNambi P, Rowe ES, McIntosh TJ
JournalBiochemistry
PubMed ID3242621
It is now well established that a number of amphiphilic molecules such as ethanol can induce the formation of the fully interdigitated gel phase in phosphatidylcholines. We have shown earlier that alcohols such as ethanol induce biphasic melting behavior in phosphatidylcholines [Rowe, E. S. (1983) Biochemistry 22, 3299-3305] but not ... More
Order in phospholipid Langmuir-Blodgett monolayers determined by total internal reflection fluorescence.
AuthorsZhai X, Kleijn JM
JournalBiophys J
PubMed ID9168040
Orientational order parameters of two diphenylhexatriene (DPH)-based fluorescent probes, 2-(3-(diphenylhexatrienyl)propanoyl)-1-hexadecanoyl-sn-glycero-3-p hosphocholine (DPHpPC) and 1-(4-trimethylammoniumphenyl)-6-phenyl-1,3,5-hexatriene (TMA-DPH), in dipalmitoylphosphatidylcholine (DPPC) Langmuir-Blodgett monolayers on quartz have been determined by total internal reflection fluorescence (TIRF). From these order parameters orientation distributions were reconstructed by the maximum-entropy method. For monolayers transferred from the liquid-condensed phase, ... More
Uptake and cellular localization of exogenous lipids by Giardia lamblia, a primitive eukaryote.
AuthorsStevens TL, Gibson GR, Adam R, Maier J, Allison-Ennis M, Das S
JournalExp Parasitol
PubMed ID9207743
Giardia lamblia trophozoites are unable to carry out de novo lipid synthesis. It is therefore likely that lipids are acquired from the small intestine of the host, in which the trophozoites are exposed to free and conjugated fatty acids, various sterols, phospholipids, bile acids, and bile-lipid mixed micelles. Here we ... More
Cell spreading and lamellipodial extension rate is regulated by membrane tension.
AuthorsRaucher D, Sheetz MP
JournalJ Cell Biol
PubMed ID10629223
Cell spreading and motility require the extension of the plasma membrane in association with the assembly of actin. In vitro, extension must overcome resistance from tension within the plasma membrane. We report here that the addition of either amphiphilic compounds or fluorescent lipids that expanded the plasma membrane increased the ... More
Dynamics of the bilayer-water interface of phospholipid vesicles and the effect of cholesterol: a picosecond fluorescence anisotropy study.
AuthorsSaito H, Araiso T, Shirahama H, Koyama T
JournalJ Biochem (Tokyo)
PubMed ID1869508
The motion of the head group of phospholipid molecules in the bilayer structure was investigated by a picosecond fluorescence anisotropy technique using a newly synthesized fluorescent phospholipid, dipalmitoyl-L-alpha-phosphatidyl-(3-p-methoxyphenyl)umbelliferone (DPPU). In this phospholipid, a coumarin derivative is attached covalently to the phosphate moiety. The motion of the acyl chain of the ... More
Sterol carrier protein-2, a new fatty acyl coenzyme A-binding protein.
AuthorsFrolov A, Cho TH, Billheimer JT, Schroeder F
JournalJ Biol Chem
PubMed ID8943231
The ability of sterol carrier protein-2 (SCP-2) to interact with long chain fatty acyl-CoAs was examined. SCP-2 bound fluorescent fatty acyl-CoAs at a single site with high affinity. Kd values for cis- and trans-parinaroyl-CoA were 4.5 and 2.8 nM, respectively. Saturated 10-18-carbon and unsaturated 14-20-carbon fatty acyl-CoAs displaced SCP-2-bound fluorescent ... More
Characterization of DNA/lipid complexes by fluorescence resonance energy transfer.
AuthorsMadeira C, Loura LM, Aires-Barros MR, Fedorov A, Prieto M
JournalBiophys J
PubMed ID14581211
Fluorescence resonance energy transfer (FRET) is a potential method for the characterization of DNA-cationic lipid complexes (lipoplexes). In this work, we used FRET models assuming a multilamellar lipoplex arrangement. The application of these models allows the determination of the distance between the fluorescent intercalator on the DNA and a membrane ... More
Order in phospholipid Langmuir-Blodgett layers and the effect of the electrical potential of the substrate.
AuthorsYang J, Kleijn JM
JournalBiophys J
PubMed ID9876144
The ordering in dipalmitoylphosphatidylcholine (DPPC) Langmuir-Blodgett monolayers and bilayers on a semiconducting indium tin oxide (ITO) surface has been investigated at the equilibrium potential of the interface and at various externally applied potentials. Second- and fourth-rank order parameters of a diphenylhexatriene (DPH) containing phospholipid probe were derived from total internal ... More
Physical states of surface and core lipids in lipid emulsions and apolipoprotein binding to the emulsion surface.
AuthorsSaito H, Minamida T, Arimoto I, Handa T, Miyajima K
JournalJ Biol Chem
PubMed ID8663047
Plasma triglyceride-rich lipoproteins vary in lipid composition during their metabolism. We investigated the effects of the lipid composition of emulsion particles, specifically those of cholesterol enrichment and core replacement (replacing core triglyceride with cholesteryl oleate), on the physical states of surface and core lipids. Steady-state and time-resolved fluorescence anisotropies were ... More
Quantitation of lateral stress in lipid layer containing nonbilayer phase preferring lipids by frequency-domain fluorescence spectroscopy.
AuthorsChen SY, Cheng KH, Van der Meer BW
JournalBiochemistry
PubMed ID1567830
Frequency-resolved fluorescence measurements have been performed to quantitate the lateral stress of the lipid layer containing nonbilayer phase preferring dioleoylphosphatidylethanolamine (DOPE). On the basis of a new rotational diffusion model, the wobbling diffusion constant (Dw), the curvature-related hopping diffusion constant (DH), and the two local orientational order parameters ([P2] and ... More
The use of fluorescence energy transfer to distinguish between poly(ethylene glycol)-induced aggregation and fusion of phospholipid vesicles.
AuthorsMorgan CG, Thomas EW, Yianni YP
JournalBiochim Biophys Acta
PubMed ID6687434
Two fluorescence energy transfer assays for phospholipid vesicle-vesicle fusion have been developed, one of which is also sensitive to vesicle aggregation. Using a combination of these assays it was possible to distinguish between vesicle aggregation and fusion as induced by poly(ethylene glycol) PEG 8000. The chromophores used were 1-(4'-carboxyethyl)-6-diphenyl-trans-1,3,5-hexatriene as ... More
Fluorescence quenching and electron spin resonance study of percolation in a two-phase lipid bilayer containing bacteriorhodopsin.
AuthorsPiknová B, Marsh D, Thompson TE
JournalBiophys J
PubMed ID9168041
The effect of bacteriorhodopsin (BR) on the percolation properties of dimyristoylphosphatidylcholine/distearoylphosphatidylcholine bilayers was examined by studying the quenching of a lipid-bound fluorophore by a lipid-bound quencher, and by spin-spin interactions of a nitroxide-labeled lipid using electron spin resonance (ESR). At the low concentrations of BR used, differential scanning calorimetry showed ... More
Novel fluorescent phospholipids for assays of lipid mixing between membranes.
AuthorsSilvius JR, Leventis R, Brown PM, Zuckermann M
JournalBiochemistry
PubMed ID3663589
A series of fluorescent phospholipids has been synthesized, by a general and versatile procedure, with various fluorescent groups attached to the methyl-terminal half of one acyl chain in an otherwise normal phospholipid structure. Phospholipids labeled with (dialkylamino)coumarin moieties, and to a slightly lesser extent those labeled with a bimane group, ... More
Uptake of fluorescent plasmalogen analogs by cultured human skin fibroblasts deficient in plasmalogen.
AuthorsLoidl J, Schwabe G, Paschke E, Paltauf F, Hermetter A
JournalBiochim Biophys Acta
PubMed ID2223814
One of the consequences of hereditary peroxisomal dysfunction in the cerebro-hepato-renal (Zellweger) syndrome (CHRS) is a dramatic decrease in the biosynthesis and cellular content of ether lipids. In the present study effects of reduced cellular plasmalogen levels on membrane-membrane interactions were investigated. Cultured CHRS fibroblasts were incubated with unilamellar phospholipid ... More
Mechanism of poly(ethylene glycol)-induced lipid transfer between phosphatidylcholine large unilamellar vesicles: a fluorescent probe study.
AuthorsWu JR, Lentz BR
JournalBiochemistry
PubMed ID2065059
Experiments were performed to assess three possible mechanisms of poly(ethylene glycol) (PEG) induced rapid lipid transfer between large unilamellar vesicles composed of dioleoylphosphatidylcholine: (1) transfer between aggregated vesicles, (2) transfer through an aqueous medium of lowered dielectric constant, and (3) transfer via a PEG carrier. The results showed that close ... More
Resolution of phospholipid conformational heterogeneity in model membranes by spin-label EPR and frequency-domain fluorescence spectroscopy.
AuthorsSquier TC, Mahaney JE, Yin JJ, Lai CS, Lakowicz JR
JournalBiophys J
PubMed ID1646658
We have utilized both fluorescent and nitroxide derivatives of stearic acid as probes of membrane structural heterogeneity in phospholipid vesicles under physiological conditions, as well as conditions of varying ionic strengths and temperatures where spectral heterogeneity has been previously observed and attributed to multiple ionization states of the probes. To ... More
Infrared and time-resolved fluorescence spectroscopic studies of the polymorphic phase behavior of phosphatidylethanolamine/diacylglycerol lipid mixtures.
AuthorsChen SY, Cheng KH
JournalChem Phys Lipids
PubMed ID2095990
Fourier transform infrared (FTIR) and time-resolved fluorescence spectroscopy have been employed to examine the structural dynamics of lipid fatty acyl chains and lipid/water interfacial region of a binary lipid mixture containing unsaturated phosphatidylethanolamine (PE) and diacylglycerol (DG). Infrared vibrational frequencies of the CH2 symmetric stretching and the C = O ... More
Time-resolved fluorescence and fourier transform infrared spectroscopic investigations of lateral packing defects and superlattice domains in compositionally uniform cholesterol/phosphatidylcholine bilayers.
Time-resolved fluorescence and Fourier transform infrared spectroscopies were used to investigate the lateral organization of lipids in compositionally uniform and fully equilibrated 1-palmitoyl-2-oleoyl-phosphatidylcholine/cholesterol (POPC/CHOL) liposomes prepared by a recently devised low-temperature trapping method. Independent fluorescence decay lifetime and rotational dynamics parameters of diphenylhexatriene (DPH) chain-labeled phosphatidylcholine (DPH-PC) in these liposomes ... More
Phospholipid order in gel- and fluid-phase cell-size liposomes measured by digitized video fluorescence polarization microscopy.
AuthorsFlorine-Casteel K
JournalBiophys J
PubMed ID2393705
Low-light digitized video fluorescence microscopy has been utilized to measure the steady-state polarized fluorescence from the membrane probe diphenylhexatriene (DPH) and its cationic and phosphatidylcholine derivatives 1-(4-trimethylammoniumphenyl)-6-phenyl-1,3,5-hexatriene (TMA-DPH) and 2-[3-(diphenylhexatrienyl)propanoyl]-3-palmitoyl-L-alpha-phosphati dylcholine (DPH-PC), respectively, in cell-size (10-70 microns) unilamellar vesicles composed of gel-or fluid-phase phospholipid. Using an inverted microscope with epi-illumination ... More
Characterization of the main transition of dinervonoylphosphocholine liposomes by fluorescence spectroscopy.
AuthorsMetso AJ, Mattila JP, Kinnunen PK
JournalBiochim Biophys Acta
PubMed ID15157624
The structural dynamics of the main phase transition of large unilamellar dinervonoylphosphocholine (DNPC) vesicles was investigated by steady state and time-resolved fluorescence spectroscopy of the membrane incorporated fluorescent lipid analog, 1-palmitoyl-2[10-(pyren-1-yl)]decanoyl-sn-glycero-3-phosphocholine (PPDPC). These data were supplemented by differential scanning calorimetry (DSC) and fluorescence anisotropy measured for 1-palmitoyl-2-(3-(diphenylhexatrienyl) propanoyl)-sn-glycero-3-phosphocholine (DPHPC). The ... More
Modulation of pig kidney Na+/K+-ATPase activity by cholesterol: role of hydration.
Cholesterol is known to affect the activity of membrane-bound enzymes, including Na(+)/K(+)-ATPase. To gain insight into the mechanism of cholesterol's effect, we have used various hydrophobic fluorescent probes which insert into different regions of the membrane bilayer and report on the degree of hydration of their environment. Specifially, we have ... More
Fusion and phase separation monitored by lifetime changes of a fluorescent phospholipid probe.
AuthorsParente RA, Lentz BR
JournalBiochemistry
PubMed ID3964657
The sensitivity of the fluorescence lifetime of 1-palmitoyl-2-[[2-[4- (6-phenyl-trans-1,3,5-hexatrienyl)phenyl]ethyl]carbonyl]- 3-sn-phosphatidylcholine (DPHpPC) to its local concentration in lipid bilayers was used to monitor both lipid mixing and phase separation occurring during membrane vesicle fusion. Vesicles containing 2 mol % DPHpPC were mixed with a 10-fold excess of vesicles devoid of probe. ... More
The rate of lipid transfer during fusion depends on the structure of fluorescent lipid probes: a new chain-labeled lipid transfer probe pair.
AuthorsMalinin VS, Haque ME, Lentz BR
JournalBiochemistry
PubMed ID11444975
A number of fluorescent probes have been used to follow membrane fusion events, particularly intermixing of lipids. None of them is ideal. The most popular pair of probes is NBD-PE and Rh-PE, in which the fluorescent groups are attached to the lipid headgroups, making them sensitive to changes in the ... More
Organization of phosphatidylcholine and sphingomyelin in the surface monolayer of low density lipoprotein and lipoprotein(a) as determined by time-resolved fluorometry.
AuthorsSommer A, Prenner E, Gorges R, Stütz H, Grillhofer H, Kostner GM, Paltauf F, Hermetter A
JournalJ Biol Chem
PubMed ID1447171
Fluorescent analogs of phosphatidylcholine (PC) and sphingomyelin (SM) labeled with diphenylhexatrienylpropionic acid (DPH) were prepared and incorporated into the surface layer of human low density lipoprotein (LDL) and lipoprotein(a) (Lp(a)). Fluorescence anisotropy measurements of DPH-PC and DPH-SM in both lipoprotein classes were carried out at different temperatures ranging from 20 ... More
Interactions between pressure and ethanol on the formation of interdigitated DPPC liposomes: a study with Prodan fluorescence.
AuthorsZeng JW, Chong PL
JournalBiochemistry
PubMed ID1892848
Steady-state fluorescence of 6-propionyl-2-(dimethylamino)naphthalene (Prodan) has been employed to study the interacting effects between ethanol and pressure on the formation of the fully interdigitated dipalmitoylphosphatidylcholine (DPPC). At 1 atm and 20 degrees C, a dramatic change in the emission spectrum of Prodan fluorescence is observed at about 1.1-1.3 M ethanol. ... More
Hydration and order in lipid bilayers.
AuthorsHo C, Slater SJ, Stubbs CD
JournalBiochemistry
PubMed ID7742324
The relationship between membrane lipid bilayer hydration and acyl chain order was investigated using time-resolved fluorescence spectroscopy. The degree of hydration in the head group region was assessed from fluorescence lifetime data along with fluorescence intensity measurements in D2O, relative to H2O buffer, using N-(5-dimethylaminonaphthalene-1-sulfonyl)dipalmitoylphosphatidylethan ola mine (dansyl-PE). The degree ... More
Enhanced rotational dynamics of the phosphorylation domain of the Ca-ATPase upon calcium activation.
AuthorsHuang S, Squier TC
JournalBiochemistry
PubMed ID9922175
We have used labeling conditions that permit the specific and covalent attachment of erythrosin isothiocyanate (Er-ITC) to Lys464 within the phosphorylation domain of the Ca-ATPase in skeletal sarcoplasmic reticulum membranes. These labeling conditions do not interfere with high-affinity ATP binding, phosphoenzyme formation, or phosphoenzyme hydrolysis [Huang, S., Negash, S., and ... More
Fluorescence anisotropy measurements of lipid order in plasma membranes and lipid rafts from RBL-2H3 mast cells.
AuthorsGidwani A, Holowka D, Baird B
JournalBiochemistry
PubMed ID11591163
Specialized plasma membrane domains known as lipid rafts participate in signal transduction and other cellular processes, and their liquid ordered (L(o)) phase appears to be important for their function. To quantify ordered lipids in biological membranes, we investigated steady-state fluorescence anisotropy of two lipid probes, 2-[3-(diphenylhexatrienyl)propanoyl]-1-hexadecanoyl-sn-glycero-3-phosphocholine (DPH-PC) and N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)-1,2-dihexadecanoyl-sn-glycero-3-phosphoethanolamine (NBD-PE). ... More
Properties of a phosphatidylcholine derivative of diphenyl hexatriene (DPH-PC) in lymphocyte membranes. A comparison with DPH and the cationic derivative TMA-DPH using static and dynamic fluorescence.
AuthorsFerretti G, Tangorra A, Zolese G, Curatola G
JournalMembr Biochem
PubMed ID8510559
Using static and dynamic fluorescence we studied the fluorescence properties of a phosphatidylcholine analog of 1,6-diphenyl-1,3,5-hexatriene (DPH-PC) incorporated in lymphocyte plasma membranes with respect to DPH and its cationic derivative 1-(4-trimethylammoniumphenyl)-6-phenyl-1,3,5-hexatriene (TMA-DPH), in order to study if phospholipid derivatives of DPH may be used to investigate structural and physicochemical properties ... More
The effects of phospholipid unsaturation and alcohol perturbation at the protein/lipid interface probed using fluorophore lifetime heterogeneity.
AuthorsHo C, Kelly MB, Stubbs CD
JournalBiochim Biophys Acta
PubMed ID8054352
The influence of phospholipid unsaturation and perturbation by alcohols, on the membrane protein/lipid interface, was probed using the fluorescence decay properties of 1,6-diphenyl-1,3,5-hexatriene (DPH) and DPH attached to the sn-2 chain of phosphatidylcholine (DPH-PC), in lipid bilayers and microsomal membranes. With microsomal membranes it was found that it was appropriate ... More
Lysophosphatidylcholine modulates catalytically important motions of the Ca-ATPase phosphorylation domain.
AuthorsHunter GW, Bigelow DJ, Squier TC
JournalBiochemistry
PubMed ID10194382
Catalytically important motions of the Ca-ATPase, modulated by the physical properties of surrounding membrane phospholipids, have been suggested to be rate-limiting under physiological conditions. To identify the nature of the structural coupling between the Ca-ATPase and membrane phospholipids, we have investigated the functional and structural effects resulting from the incorporation ... More
Modulation of the physical state of cellular cholesteryl esters by 4,4'-(isopropylidenedithio)bis(2,6-di-t-butylphenol) (probucol).
AuthorsMcLean LR, Thomas CE, Weintraub B, Hagaman KA
JournalJ Biol Chem
PubMed ID1601894
The effect of 4,4'-(isopropylidenedithio)bis(2,6-di-t-butylphenol) (probucol) on cholesteryl ester physical state was examined in dry mixtures, phospholipid-containing dispersions, and cells. Probucol has little effect on the solid to isotropic transition of cholesteryl oleate, but broadens and decreases the enthalpy of the liquid-crystalline transitions at concentrations as low as 1-2 mol %. ... More
Fluorescence dynamics of diphenyl-1,3,5-hexatriene-labeled phospholipids in bilayer membranes.
AuthorsPap EH, ter Horst JJ, van Hoek A, Visser AJ
JournalBiophys Chem
PubMed ID8110960
A comparative study of the dynamical fluorescence properties of three phosphatidylcholines having a diphenyl-1,3,5-hexatriene (DPH) group attached at different depths from the head group incorporated into membrane vesicles has been carried out. The probes were covalently attached to the sn-2 position of the glycerol part of the phosphatidylcholine via either ... More
Effects of lateral diffusion on the fluorescence anisotropy in hexagonal lipid phases. II. An experimental study.
AuthorsChen SY, Cheng KH, Van der Meer BW, Beechem JM
JournalBiophys J
PubMed ID2275967
The polymorphic phase behavior of unsaturated phosphatidylethanolamine (PE)/diacylglycerol (DG) binary lipid mixtures was investigated by the use of time-resolved fluorescence anisotropy. Using a fluorescent lipid, 1-palmitoyl-2-[[2-[4-(6-phenyl-trans-1,3,5-hexatrienyl)phenylethyl] carbonyl]3-sn-phosphatidyl-choline (DPH-PC), the orientational order and rotational dynamics of the above lipid mixtures in the liquid crystalline lamellar (L alpha) and inverted hexagonal (HII) ... More
Analysis of cell membrane micro-heterogeneity using the fluorescence lifetime of DPH-type fluorophores.
AuthorsHo C, Williams BW, Stubbs CD
JournalBiochim Biophys Acta
PubMed ID1547264
Heterogeneity in the lipid organization in lipid bilayers and cell membranes was probed by using the fluorescence decay of 1,6-diphenyl-1,3,5-hexatriene (DPH) and DPH attached to the sn-2 position of phosphatidylcholine (DPH-PC). In the presence of protein, it is proposed that the bulk lipids and boundary lipids can potentially provide distinct ... More