Abstract:
:The interaction of the nonionic surfactant dodecylmaltoside (DM) with phosphatidylcholine liposomes was investigated. Permeability alterations were detected as a change in 5(6)-carboxyfluorescein released from the interior of vesicles and bilayer solubilization as a decrease in the static light scattered by liposome suspensions. This surfactant showed higher capacity to saturate and solubilize PC liposomes and greater affinity with these structures than those reported for the octyl glucoside. At subsolubilizing level an initial maximum in the bilayer/water partitioning (K) followed by an abrupt decrease of this parameter occurred as the effective molar ratio of surfactant to phospholipid in bilayers (Re) rose. However, at solubilizing level a direct dependence was established between both parameters. A direct correlation took place in the initial interaction steps (Re up to 0.28) between the growth of vesicles, their fluidity, and Re. A similar direct dependence was established during solubilization (Re range from 0.9 to 1.7) between the decrease in both the surfactant-PC aggregate size, the light scattering of the system, and Re (composition of aggregates). The fact that the free DM concentration at subsolubilizing and solubilizing levels showed values lower than and similar to its critical micelle concentration indicates that permeability alterations and solubilization were determined, respectively, by the action of surfactant monomer and by the formation of mixed micelles.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
de la Maza A,Parra JLdoi
10.1016/S0006-3495(97)78812-Xsubject
Has Abstractpub_date
1997-04-01 00:00:00pages
1668-75issue
4eissn
0006-3495issn
1542-0086pii
S0006-3495(97)78812-Xjournal_volume
72pub_type
杂志文章abstract::Deuterium and phosphorus nuclear magnetic resonance (NMR) has been used to investigate the dynamics of slow motional processes induced in bilayer cardiolipin upon binding with cytochrome c. 31P NMR line shapes suggest that protein binding induces less restricted, isotropic-like motions in the lipid phosphates within t...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(93)81048-8
更新日期:1993-07-01 00:00:00
abstract::Noncanonical DNA structures that retain programmability and structural predictability are increasingly being used in DNA nanotechnology applications, in which they offer versatility beyond traditional Watson-Crick interactions. The d(CGA) triplet repeat motif is structurally dynamic and can transition between parallel...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2020.09.002
更新日期:2020-10-20 00:00:00
abstract::During the first 2 hours of Drosophila development, precisely orchestrated nuclear cleavages, cytoskeletal rearrangements, and directed membrane growth lead to the formation of an epithelial sheet around the yolk. The newly formed epithelium remains relatively quiescent during the next hour as it is patterned by mater...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2020.03.010
更新日期:2020-05-19 00:00:00
abstract::Interpretation of fluorescence anisotropy decay for the case of restricted rotational diffusion often requires a model. To investigate the extent of model dependence, two models are compared: a strict cone model, in which a fluorescent probe wobbles uniformly within a cone, and a Gaussian model, where the stationary d...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(82)84692-4
更新日期:1982-02-01 00:00:00
abstract::The spontaneous folding of two Neisseria outer membrane proteins, opacity-associated (Opa)(60) and Opa(50) into lipid vesicles was investigated by systematically varying bulk and membrane properties. Centrifugal fractionation coupled with sodium dodecyl sulfate polyacrylamide gel electrophoresis mobility assays enable...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2011.03.025
更新日期:2011-05-04 00:00:00
abstract::Activation of skeletal muscle ryanodine receptors (RyRs) by suramin and disulfonic stilbene derivatives (Diisothiocyanostilbene-2',2'-disulfonic acid (DIDS), 4,4'-dibenzamidostilbene-2,2'-disulfonic acid (DBDS),and 4,4'-dinitrostilbene-2,2'-disulfonic acid (DNDS)) was investigated using planar bilayers. One reversible...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(03)74976-5
更新日期:2003-03-01 00:00:00
abstract::Biological systems often have to measure extremely low concentrations of chemicals with high precision. When dealing with such small numbers of molecules, the inevitable randomness of physical transport processes and binding reactions will limit the precision with which measurements can be made. An important question ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2013.12.030
更新日期:2014-02-18 00:00:00
abstract::Bax and Bid are proapoptotic proteins of the Bcl-2 family that regulate the release of apoptogenic factors from mitochondria. Although they localize constitutively in the cytoplasm, their apoptotic function is exerted at the mitochondrial outer membrane, and is related to their ability to form transbilayer pores. Here...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.058008
更新日期:2005-06-01 00:00:00
abstract::To assay cell cycle progression in synchronized culture of yeast we have applied dielectric spectroscopy to its real-time monitoring. The dielectric monitoring is based on the electromagnetic induction method, regarded as a nonelectrode method, which has resolved the problems encountered in measurements with metal ele...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(99)77487-4
更新日期:1999-06-01 00:00:00
abstract::Singlet-triplet mixing in the initial radical-pair state, P[unk]I[unk], of photosynthetic bacterial reaction centers is due to the hyperfine mechanism at low magnetic fields and both the hyperfine and Deltag mechanisms at high magnetic fields (>1 kG). Since the hyperfine field felt by the electron spins in P[unk]I[unk...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(87)83421-5
更新日期:1987-06-01 00:00:00
abstract::We investigated the accessibility to protons and thiol-directed reagents of a cysteine substituted at position 338 in transmembrane segment 6 (TM6) of CFTR to test the hypothesis that T338 resides in the pore. Xenopus oocytes expressing T338C CFTR exhibited pH-dependent changes in gCl and I-V shape that were specific ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.050534
更新日期:2004-12-01 00:00:00
abstract::We investigated whether the cysteine residues in Shaker potassium (K+) channels are essential for activation and inactivation gating or for modulation of activation gating by external zinc (Zn2+). Mutants of the Shaker K+ channel were prepared in which all seven cysteine residues were replaced (C-less). These changes ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/s0006-3495(94)80843-4
更新日期:1994-03-01 00:00:00
abstract::The process of clathrin self-assembly into closed shells with the Fullerene structure is investigated. It is argued that the shell size distribution is governed by the kinetics of assembly and depends on the rate of growth controlled by the free clathrin concentration. The particularly abundant small structures--the "...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/s0006-3495(97)78729-0
更新日期:1997-02-01 00:00:00
abstract::KATP channels assemble from four regulatory SUR1 and four pore-forming Kir6.2 subunits. At the single-channel current level, ATP-dependent gating transitions between the active burst and the inactive interburst conformations underlie inhibition of the KATP channel by intracellular ATP. Previously, we identified a slow...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(04)74269-1
更新日期:2004-04-01 00:00:00
abstract::The properties of vesicle membranes prepared from 16:0-SM, 16:0-DHSM, or DPPC were characterized using steady-state and time-resolved fluorescence spectroscopy and different fluorescent reporter molecules. The acyl-chain region was probed using free and phospholipid-bound 1,6-diphenyl-1,3,5-hexatriene. 16:0-DHSM was f...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(03)74915-7
更新日期:2003-02-01 00:00:00
abstract::The bovine eye lens protein, alpha L crystallin, has been studied with photon correlation spectroscopy and statical light scattering in the concentration range up to 200 g/l in different solvent conditions. At higher concentration (c greater than 70 g/l) the scattering behavior is quite complicated, which results in n...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(85)83955-2
更新日期:1985-05-01 00:00:00
abstract::Fluorescence lifetime imaging microscopy is used to demonstrate that different loads applied to a muscle fiber change the microenvironment of the nucleotide binding pocket of myosin. Permeabilized skeletal muscle fibers in rigor were labeled with a fluorescent ATP analog, 3'-DEAC-propylenediamine (pda)-ATP (3'-O-{N-[3...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2010.07.052
更新日期:2010-10-06 00:00:00
abstract::To map the binding sites involved in channel formation, synthetic peptides representing sequences of connexin 32 were tested for their ability to inhibit cell-cell channel formation. Both large peptides representing most of the two presumed extracellular loops of connexin32 and shorter peptides representing subsets of...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(94)80663-0
更新日期:1994-11-01 00:00:00
abstract::Cholesterol is abundant in plasma membranes and exhibits a variety of interactions throughout the membrane. Chemical potential accounts for thermodynamic consequences of molecular interactions, and quantifies the effective concentration (i.e., activity) of any substance participating in a process. We have developed, t...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2017.12.042
更新日期:2018-02-27 00:00:00
abstract::Coliphage T4 was used as a model system to study the mechanism of biological inactivation produced by tritium decay. Experimentally, tritiated precursors were incorporated into phage DNA (thymidine-(3)H) or into phage protein ((3)H-amino acids). The ratio of killing efficiencies for decays originating in phage DNA to ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(68)86537-3
更新日期:1968-09-01 00:00:00
abstract::Molecular dynamics simulations are presented for a Thermus aquaticus (Taq) DNA polymerase I complex (consisting of the protein, the primer-template DNA strands, and the incoming nucleotide) subjected to external forces. The results obtained with a force applied to the DNA template strand provide insights into the effe...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.103.039313
更新日期:2004-09-01 00:00:00
abstract::As sketched in Fig. 1, a current molecular dynamics computer simulation of a lipid bilayer fails to capture significant features of the macroscopic system, including long wavelength undulations. Such fluctuations are intrinsically connected to the value of the macroscopic (or thermodynamic) surface tension (cf. Eqs. 1...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(96)79337-2
更新日期:1996-09-01 00:00:00
abstract::The use of the long-lived fluorescence probe coronene (mean value of tau(FL) approximately 200 ns) is described for investigating submicrosecond lipid dynamics in DPPC model bilayer systems occurring below the lipid phase transition. Time-resolved fluorescence emission anisotropy decay profiles, measures as a function...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(96)79384-0
更新日期:1996-10-01 00:00:00
abstract::The supertwisted, double-stranded, replicative intermediate of øX174 DNA (RFI) has been used to determine whether one of the two strands of the double helix is uniquely sensitive to induction of single-strand breaks by ionizing radiation. This could result from a particularly sensitive base sequence or a transfer of e...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/s0006-3495(73)85970-3
更新日期:1973-01-01 00:00:00
abstract::Purple membranes were adsorbed on freestanding lipid bilayers, termed nano-black lipid membranes (nano-BLMs), suspending the pores of porous alumina substrates with average pore diameters of 280 nm. Nano-BLMs were obtained by first coating the upper surface of the highly ordered porous alumina substrates with a thin g...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.059550
更新日期:2005-08-01 00:00:00
abstract::The S4 transmembrane domain of the family of voltage-gated ion channels is generally thought to be the voltage sensor, whose translocation by an applied electric field produces the gating current. Experiments on hSkMI Na(+) channels and both Shaker and EAG K(+) channels indicate which S4 residues cross the membrane-so...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(03)74708-0
更新日期:2003-11-01 00:00:00
abstract::Here it is reported that aggrecan, the highly negatively charged macromolecule in the cartilage extracellular matrix, undergoes Ca(2+)-mediated self-adhesion after static compression even in the presence of strong electrostatic repulsion in physiological-like solution conditions. Aggrecan was chemically end-attached o...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.128389
更新日期:2008-11-15 00:00:00
abstract::A microscopic model of passive transverse mass transport of small solutes in the viable epidermal layer of human skin is formulated on the basis of a hexagonal array of cells (i.e., keratinocytes) bounded by 4-nm-thick, anisotropic lipid bilayers and separated by 1-μm layers of extracellular fluid. Gap junctions and t...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2013.03.056
更新日期:2013-05-21 00:00:00
abstract::The circadian clocks keeping time in many living organisms rely on self-sustained biochemical oscillations entrained by external cues, such as light, to the 24-h cycle induced by Earth's rotation. However, environmental cues are unreliable due to the variability of habitats, weather conditions, or cue-sensing mechanis...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2011.04.043
更新日期:2011-06-08 00:00:00
abstract::This paper examines "realistic" pores, i.e., ones that are neither symmetric nor of uniform diameter. Methods are described that permit estimation of the image potential for an ion in an aqueous pore spanning a lipid membrane and for the electric field produced in such a pore when a transmembrane potential is applied....
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/s0006-3495(84)84258-7
更新日期:1984-06-01 00:00:00