Interaction of melittin with membrane cholesterol: a fluorescence approach.

abstract：:EXACT FORMULAS ARE DERIVED FOR THE ENERGY CHANGE OF A DIPOLE SYSTEM WITH TWO ENERGY STATES (OR BANDS) IN A CHANGING FIELD IN TWO CASES: (a) no dipole flip-flop and (b) dipole flip-flop caused by stimulation. Based on these formulas, the positive and negative heats are calculated. The results are in good agreement with...

journal_title：Biophysical journal

authors： Wei LY

更新日期：1972-09-01 00:00:00

abstract：:Single-molecule studies allow the study of subtle activity differences due to local folding in proteins, but are time consuming and difficult because only a few molecules are observed in one experiment. We developed an assay where we can simultaneously measure the activity of hundreds of individual molecules. The assa...

journal_title：Biophysical journal

authors： Lee AI,Brody JP

更新日期：2005-06-01 00:00:00

abstract：:Cytotoxic lymphocytes are key elements of the immune system that are primarily responsible for targeting cells infected with intracellular pathogens, or cells that have become malignantly transformed. Target cells are killed mainly via lymphocyte exocytosis of specialized lysosomes containing perforin, a pore-forming ...

journal_title：Biophysical journal

authors： Woodsworth DJ,Dunsing V,Coombs D

更新日期：2015-08-04 00:00:00

abstract：:Many proteins "bind" DNA through positively charged amino acids on their surfaces. However, to overcome significant energetic and topological obstacles, proteins that bend or package DNA might also modulate the stiffness that is generated by repulsions between phosphates within DNA. Much previous work describes how io...

journal_title：Biophysical journal

authors： Podestà A,Indrieri M,Brogioli D,Manning GS,Milani P,Guerra R,Finzi L,Dunlap D

更新日期：2005-10-01 00:00:00

abstract：:The potassium selective, inward rectifier current (IK1) is known to be responsible for maintaining the resting membrane potential of quiescent ventricular myocytes. However, the contribution of this current to the different phases of the cardiac action potential has not been adequately established. In the present stud...

journal_title：Biophysical journal

authors： Ibarra J,Morley GE,Delmar M

更新日期：1991-12-01 00:00:00

abstract：:The inositol (1,4,5)-trisphosphate receptor (InsP(3)R) is an intracellular calcium (Ca(2+)) release channel that plays a crucial role in cell signaling. In Drosophila melanogaster a single InsP(3)R gene (itpr) encodes a protein (DmInsP(3)R) that is approximately 60% conserved with mammalian InsP(3)Rs. A number of itpr...

journal_title：Biophysical journal

authors： Srikanth S,Wang Z,Tu H,Nair S,Mathew MK,Hasan G,Bezprozvanny I

更新日期：2004-06-01 00:00:00

abstract：:Diacylglycerol kinase ε (DGKε) is a membrane-bound enzyme that catalyzes the ATP-dependent phosphorylation of diacylglycerol to form phosphatidic acid (PA) in the phosphatidylinositol cycle. DGKε lacks a putative regulatory domain and has recently been reported to be regulated by highly curved membranes. To further st...

journal_title：Biophysical journal

authors： Bozelli JC Jr,Yune J,Hou YH,Chatha P,Fernandes A,Cao Z,Tong Y,Epand RM

更新日期：2020-02-25 00:00:00

abstract：:The structure of polyamines-DNA precipitates was studied by x-ray diffraction. Precise measurements of the interhelix distance a(H) were obtained at different NaCl, polyamine, and DNA concentrations. Most of the results were obtained using spermine and few others using spermidine. The precipitates are liquid crystalli...

journal_title：Biophysical journal

authors： Raspaud E,Durand D,Livolant F

更新日期：2005-01-01 00:00:00

abstract：:The biophysical characterization of nonfunctional protein aggregates at physiologically relevant temperatures is much needed to gain deeper insights into the kinetic and thermodynamic relationships between protein folding and misfolding. Dynamic and static laser light scattering have been employed for the detection an...

journal_title：Biophysical journal

authors： Chow C,Kurt N,Murphy RM,Cavagnero S

更新日期：2006-01-01 00:00:00

abstract：:The S4 segments of voltage-gated sodium channels are important parts of the voltage-sensing elements of these proteins. Furthermore, the addition of the isolated S4 polypeptide to planar lipid bilayers results in stepwise increases of ion conductivity. In order to gain insight into the mechanisms of pore formation by ...

journal_title：Biophysical journal

authors： Mattila K,Kinder R,Bechinger B

更新日期：1999-10-01 00:00:00

abstract：:We have examined the mechanisms underlying the voltage sensitivity of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate receptors in voltage-clamped outside-out patches and whole cells taken from the nucleus magnocellularis of the chick. Responses to either glutamate or kainate had outwardly rectifying current-volt...

journal_title：Biophysical journal

authors： Raman IM,Trussell LO

更新日期：1995-11-01 00:00:00

abstract：:Although cell-cell interactions are known to significantly affect the kinetics of intracellular ice formation (IIF) during tissue freezing, this effect is not well understood. Progress in elucidating the mechanism and role of intercellular ice propagation in tissue freezing has been hampered in part by limitations in ...

journal_title：Biophysical journal

authors： Irimia D,Karlsson JO

更新日期：2005-01-01 00:00:00

abstract：:Cell-mediated contraction plays a critical role in many physiological and pathological processes, notably organized contraction during wound healing. Implantation of an appropriately formulated (i.e., mean pore size, chemical composition, degradation rate) three-dimensional scaffold into an in vivo wound site effectiv...

journal_title：Biophysical journal

authors： Harley BA,Freyman TM,Wong MQ,Gibson LJ

更新日期：2007-10-15 00:00:00

abstract：:We examined four cardiomyopathy-causing mutations of troponin I that appear to disturb function by altering the distribution of thin filament states. The R193H (mouse) troponin I mutant had greater than normal actin-activated myosin-S1 ATPase activity in both the presence and absence of calcium. The rate of ATPase act...

journal_title：Biophysical journal

authors： Mathur MC,Kobayashi T,Chalovich JM

更新日期：2009-03-18 00:00:00

abstract：:We describe a combined use of experimental and simulation techniques to configure side chains in a coiled coil structure. As already demonstrated in a previous work, x-ray diffraction patterns from hard alpha-keratin fibers in the 5.15 A meridian zone reflect the global configuration of the chi(1) dihedral angle of th...

journal_title：Biophysical journal

authors： Briki F,Doucet J,Etchebest C

更新日期：2002-10-01 00:00:00

abstract：:We report the first time-resolved study of the two-dimensional x-ray diffraction pattern during active contraction in insect flight muscle (IFM). Activation of demembranated Lethocerus IFM was triggered by 1.5-2.5% step stretches (risetime 10 ms; held for 1.5 s) giving delayed active tension that peaked at 100-200 ms....

journal_title：Biophysical journal

authors： Tregear RT,Edwards RJ,Irving TC,Poole KJ,Reedy MC,Schmitz H,Towns-Andrews E,Reedy MK

更新日期：1998-03-01 00:00:00

abstract：:The suprachiasmatic nucleus governs daily variations of physiology and behavior in mammals. Within single neurons, interlocked transcriptional/translational feedback loops generate circadian rhythms on the molecular level. We present a mathematical model that reflects the essential features of the mammalian circadian ...

journal_title：Biophysical journal

authors： Becker-Weimann S,Wolf J,Herzel H,Kramer A

更新日期：2004-11-01 00:00:00

abstract：:We present here the parmbsc0 force field, a refinement of the AMBER parm99 force field, where emphasis has been made on the correct representation of the alpha/gamma concerted rotation in nucleic acids (NAs). The modified force field corrects overpopulations of the alpha/gamma = (g+,t) backbone that were seen in long ...

journal_title：Biophysical journal

authors： Pérez A,Marchán I,Svozil D,Sponer J,Cheatham TE 3rd,Laughton CA,Orozco M

更新日期：2007-06-01 00:00:00

abstract：:Pure Michaelis-Menten enzymes have been studied (i.e., enzymes with a hyperbolic (S, V) behavior in a well-stirred solution). When such enzymes are associated with a structure in vitro, even in the simplest conceivable form (immobilization in a homogeneous gel), they can produce enzymic or transport reactions with man...

journal_title：Biophysical journal

authors： Vincent JC,Thellier M

更新日期：1983-01-01 00:00:00

abstract：:Quasilongitudinal sound velocities and the second-order elastic moduli of tetragonal hen egg-white lysozyme crystals were determined as a function of relative humidity (RH) by Brillouin scattering. In hydrated crystals the measured sound velocities in the [110] plane vary between 2.12 +/- 0.03 km/s along the [001] dir...

journal_title：Biophysical journal

authors： Speziale S,Jiang F,Caylor CL,Kriminski S,Zha CS,Thorne RE,Duffy TS

更新日期：2003-11-01 00:00:00

abstract：:The capability to image single microbial cell surfaces at nanometer scale under native conditions would profoundly impact mechanistic and structural studies of pathogenesis, immunobiology, environmental resistance, and biotransformation. Here, using in vitro atomic force microscopy, we have directly visualized high-re...

journal_title：Biophysical journal

authors： Plomp M,Leighton TJ,Wheeler KE,Malkin AJ

更新日期：2005-01-01 00:00:00

abstract：:Nonconfluent fibroblasts are relatively depolarized when compared with confluent fibroblasts, and transient hyperpolarizations result from a range of external stimuli as well as internal cellular activities. This electrical activity ceases, along with growth and mitogenic activity, when the cells become confluent. A c...

journal_title：Biophysical journal

authors： Stockbridge LL,French AS

更新日期：1988-07-01 00:00:00

abstract：:We modeled two different mechanisms, a shunting conductance and a slow sodium inactivation, to test whether they could modulate the active propagation of a train of action potentials in a dendritic tree. Computer simulations, using a compartmental model of a pyramidal neuron, suggest that each of these two mechanisms ...

journal_title：Biophysical journal

authors： Migliore M

更新日期：1996-11-01 00:00:00

abstract：:We investigate the conditions under which nonideality in solution influences the Donnan equilibrium. Of the various parameters that characterize this equilibrium, the osmotic pressure established across the Donnan membrane is found to be particularly sensitive to intermolecular interactions between the diffusible and ...

journal_title：Biophysical journal

authors： Stell G,Joslin CG

更新日期：1986-11-01 00:00:00

abstract：:Many traditional approaches to the analysis of sedimentation velocity data work poorly with data for low-molecular-weight solutes, which have sedimentation boundaries that are severely broadened by diffusion. An approach that has previously had some success is to directly fit these broad boundaries to approximate solu...

journal_title：Biophysical journal

authors： Philo JS

更新日期：1997-01-01 00:00:00

abstract：:We derive the statistics of the signals generated by shape fluctuations of large molecules studied by feedback tracking microscopy. We account for the influence of intramolecular dynamics on the response of the tracking system and derive a general expression for the fluorescence autocorrelation function that applies w...

journal_title：Biophysical journal

authors： McHale K,Mabuchi H

更新日期：2010-07-07 00:00:00

abstract：:A comparative analysis of two models of anisotropic reactivity in bimolecular diffusion-controlled reaction kinetics is presented. One is the conventional model of reactive patches (MRP), where the surface of a molecule is assumed to be reactive over a certain region (circular patch) with the rest of the surface being...

journal_title：Biophysical journal

authors： Barzykin AV,Shushin AI

更新日期：2001-05-01 00:00:00

abstract：:The observation of biological processes at the molecular scale in real time requires high spatial and temporal resolution. Magnetic tweezers are straightforward to implement, free of radiation or photodamage, and provide ample multiplexing capability, but their spatiotemporal resolution has lagged behind that of other...

journal_title：Biophysical journal

authors： Dulin D,Cui TJ,Cnossen J,Docter MW,Lipfert J,Dekker NH

更新日期：2015-11-17 00:00:00

abstract：:Purple photosynthetic bacteria harvest light using pigment-protein complexes which are often arranged in pseudo-organelles called chromatophores. A model of a chromatophore from Rhodospirillum photometricum was constructed based on atomic force microscopy data. Molecular-dynamics simulations and quantum-dynamics calcu...

journal_title：Biophysical journal

authors： Chandler DE,Strümpfer J,Sener M,Scheuring S,Schulten K

更新日期：2014-06-03 00:00:00

abstract：:Cellular processes are noisy due to the stochastic nature of biochemical reactions. As such, it is impossible to predict the exact quantity of a molecule or other attributes at the single-cell level. However, the distribution of a molecule over a population is often deterministic and is governed by the underlying regu...

journal_title：Biophysical journal

authors： Li B,You L

更新日期：2014-09-02 00:00:00