Abstract:
:The nanomechanical response of supported lipid bilayers has been studied by force spectroscopy with atomic force microscopy. We have experimentally proved that the amount of ions present in the measuring system has a strong effect on the force needed to puncture a 1,2-dimyristoyl-sn-glycero-3-phosphocholine bilayer with an atomic force microscope tip, thus highlighting the role that monovalent cations (so far underestimated, e.g., Na(+)) play upon membrane stability. The increase in the yield threshold force has been related to the increase in lateral interactions (higher phospholipid-phospholipid interaction, decrease in area per lipid) promoted by ions bound into the membrane. The same tendency has also been observed for other phosphatidylcholine bilayers, namely, 2-dilauroyl-sn-glycero-3-phosphocholine, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine, and 1,2-dioleoyl-sn-3-phosphocholine, and also for phosphatidylethanolamine bilayers such as 1-palmitoyl-2-oleoyl-sn-3-phosphoethanolamine. Finally, this effect has been also tested on a natural lipid bilayer (Escherichia coli lipid extract), showing the same overall tendency. The kinetics of the process has also been studied, together with the role of water upon membrane stability and its effect on membrane nanomechanics. Finally, the effect of the chemical structure of the phospholipid molecule on the nanomechanical response of the membrane has also been discussed.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Garcia-Manyes S,Oncins G,Sanz Fdoi
10.1529/biophysj.105.064030subject
Has Abstractpub_date
2005-09-01 00:00:00pages
1812-26issue
3eissn
0006-3495issn
1542-0086pii
S0006-3495(05)72826-5journal_volume
89pub_type
杂志文章abstract::We have used fluorescence-quenching measurements to characterize the partitioning of a variety of indolyl-labeled phospho- and sphingolipids between gel or liquid-ordered and liquid-disordered lipid domains in several types of lipid bilayers where such domains coexist. In both cholesterol-free and cholesterol-containi...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(03)74857-7
更新日期:2003-01-01 00:00:00
abstract::We study dsDNA-RecA interactions by exerting forces in the pN range on single DNA molecules while the interstrand topological state is controlled owing to a magnetic tweezers setup. We show that unwinding a duplex DNA molecule induces RecA polymerization even at moderate force. Once initial polymerization has nucleate...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.043059
更新日期:2004-10-01 00:00:00
abstract::The triplet state absorption and phosphorescence of Zn and Pd derivatives of myoglobin were compared. Both metal derivatives exhibit long triplet state lifetimes at room temperature, but whereas the Pd derivative showed exponential decay and an isosbestic point in the transient absorption spectra, the decay of the Zn ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(90)82363-8
更新日期:1990-07-01 00:00:00
abstract::Effects of alkali cations on the nuclear magnetic resonance intensity of 23Na were studied in rat liver homogenate. The loss in the resonance intensity of 23Na in the homogenate was able to be divided into two components, one of which is abolished by the addition of Cs+ ("Cs-sensitive component"), the other being inse...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(76)85779-7
更新日期:1976-12-01 00:00:00
abstract::We investigate the microsecond-timescale kinetics of the RNA hairpin ga*cUUCGguc. The fluorescent nucleotide 2-aminopurine (a*) reports mainly on base stacking. Ten kinetic traces and the temperature denaturation curve are globally fitted to four-state models of the free-energy surface. In the best-fitting sequential ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2009.06.035
更新日期:2009-09-02 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
pub_type: 杂志文章
doi:10.1529/biophysj.104.055053
更新日期:2005-06-01 00:00:00
abstract::Optical potentiometric indicators have been used to monitor the transmembrane electrical potential (Em) of many cells and organelles. A better understanding of the mechanisms of dye response is needed for the design of dyes with improved responses and for unambiguous interpretation of experimental results. This paper ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(90)82603-5
更新日期:1990-04-01 00:00:00
abstract::Platinum-containing molecules are widely used as anticancer drugs. These molecules exert cytotoxic effects by binding to DNA through various mechanisms. The binding between DNA and platinum-based drugs hinders the opening of DNA, and therefore, DNA duplication and transcription are severely hampered. Overall, impeding...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2016.02.030
更新日期:2016-05-24 00:00:00
abstract::The process by which an organism changes the composition of its membranal fatty acids in response to growth temperature, so as to maintain optimal membrane functioning, is known as homeoviscous adaptation (HA). One expression of HA is the constancy of the fluorescence polarization (P) of the lipophilic probe 1,6-diphe...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(90)82578-9
更新日期:1990-03-01 00:00:00
abstract::Many complex cellular processes from mitosis to cell motility depend on the ability of the cytoskeleton to generate force. Force-generating systems that act on elastic cytoskeletal elements are prone to oscillating instabilities. In this work, we have measured spontaneous shape and movement oscillations in motile fish...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2009.10.058
更新日期:2010-03-17 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::Nanopatterned surfaces are believed to kill bacteria through physical deformation, a mechanism that has immense potential against biochemical resistance. Because of its elusive nature, this mechanism is mostly understood through biophysical modeling. Problematically, accurate descriptions of the contact mechanics and ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2020.12.003
更新日期:2021-01-19 00:00:00
abstract::Cell adhesion to the extracellular matrix (ECM) is highly active and plays a crucial role in various physiological functions. The active response of cells to physicochemical cues has been universally discovered in multiple microenvironments. However, the mechanisms to rule these active behaviors of cells are still poo...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2020.04.016
更新日期:2020-06-02 00:00:00
abstract::The UV-visible absorption and magnetic circular dichroism (MCD) spectra of the ferric, ferrous, CO-ligated forms and kinetic photolysis intermediates of the tetraheme electron-transfer protein cytochrome c3 (Cc3) are reported. Consistent with bis-histidinyl axial coordination of the hemes in this Class III c-type cyto...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(93)81226-8
更新日期:1993-10-01 00:00:00
abstract::A simple method of simulating cell kinetics experiments, suitable for use on small generally available computers and capable of any degree of accuracy without increase of store required, is described. No assumption is necessary as to cycle-time distribution; the computer program, after being adjusted to generate perce...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(72)86172-1
更新日期:1972-11-01 00:00:00
abstract::The efficiency of various patterns of pulsatile stimulation is determined in a model in which a receptor becomes desensitized in the presence of its stimulatory ligand. The effect of stochastic or chaotic changes in the duration and/or interval between successive pulses in a series of square-wave stimuli is investigat...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(92)81824-6
更新日期:1992-01-01 00:00:00
abstract::This study reports the solid-state NMR spectroscopic characterization of the amino-proximate transmembrane domain (TM-A) of a diverged microsomal delta12-desaturase (CREP-1) in a phospholipid bilayer. A series of TM-A peptides were synthesized with 2H-labeled side chains (Ala-53, -56, and -63, Leu-62, Val-50), and the...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.067884
更新日期:2006-02-15 00:00:00
abstract::Molecular recognition between biotinylated bovine serum albumin and polyclonal, biotin-directed IG antibodies has been measured directly under various buffer conditions using an atomic force microscope (AFM). It was found that even highly structured molecules such as IgG antibodies preserve their specific affinity to ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(96)79814-4
更新日期:1996-05-01 00:00:00
abstract::Phospholipids with covalently attached poly(ethylene glycol) (PEG lipids) are commonly used for the preparation of long circulating liposomes. Although it is well known that lipid/PEG-lipid mixed micelles may form above a certain critical concentration of PEG-lipid, little is known about the effects of PEG-lipids on l...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(97)78066-4
更新日期:1997-07-01 00:00:00
abstract::Molecular dynamics simulations have been applied to the DNA octamer d(GCGCA-GAAC). d(GTTCGCGC), which has an adenine bulge at the center to determine the pathway for interconversion between the stacked and extended forms. These forms are known to be important in the molecular recognition of bulges. From a total of ~35...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(01)75705-0
更新日期:2001-07-01 00:00:00
abstract::Spatial patterning of biochemical cues on the micro- and nanometer scale controls numerous cellular processes such as spreading, adhesion, migration, and proliferation. Using force microscopy we show that the lateral spacing of individual integrin receptor-ligand bonds determines the strength of cell adhesion. For spa...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2009.11.001
更新日期:2010-02-17 00:00:00
abstract::Helicobacter pylori arginase, a bimetallic enzyme, is crucial for pathogenesis of the bacterium in human stomach. Despite conservation of the signature motifs in all arginases, the H. pylori homolog has a non-conserved motif (153ESEEKAWQKLCSL165), whose role was recently shown to be critical for its stability and func...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2017.02.009
更新日期:2017-03-28 00:00:00
abstract::Structure factor amplitudes and phases can be computed directly from electron cryomicroscopy images. Inherent aberrations of the electromagnetic lenses and other instrumental factors affect the structure factors, however, resulting in decreased accuracy in the determined three-dimensional reconstruction. In contrast, ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(99)77381-9
更新日期:1999-04-01 00:00:00
abstract::Phase-resolved monitoring of photoacoustic signals can provide information about the depth profile of a sample. We describe an application of this principle to determine the depth profiles of ligands and antitumor agents in mammalian cells. Measurements of the in-phase and quadrature components of the photoacoustic sp...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(97)78881-7
更新日期:1997-05-01 00:00:00
abstract::Computations on sodium channel gating were conducted using a closed-open-inactivated coupled kinetic scheme. The time constant of inactivation (tauh) derives a voltage dependency from coupling to voltage-dependent activation even when rate constants between inactivated and other states are strictly voltage independent...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(99)77408-4
更新日期:1999-05-01 00:00:00
abstract::Skeletal muscle contraction is a canonical example of motor-driven force generation. Despite the long history of research in this topic, a mechanistic explanation of the collective myosin force generation is lacking. We present a theoretical model of muscle contraction based on the conformational movements of individu...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.056846
更新日期:2005-06-01 00:00:00
abstract::The rate of muscle force redevelopment after release-restretch protocols has previously been interpreted using a simple two-state cross-bridge cycling model with rate constants for transitions between non-force-bearing and force-bearing states, f, and between force-bearing and non-force-bearing states, g. Changes in t...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(97)78664-8
更新日期:1997-01-01 00:00:00
abstract::The diffusion of Ca as it converges to the external mouth of a Ca channel is examined. Diffusional limitation on Ca ions entering Ca channels during current flow, cause local extracellular Ca depletions. Such extracellular Ca depletions have been reported in cardiac muscle. The cardiac sarcolemma has a large number of...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(91)82284-6
更新日期:1991-03-01 00:00:00
abstract::Dim-light vision is mediated by retinal rod cells. Rhodopsin (R), a G-protein-coupled receptor, switches to its active form (R(∗)) in response to absorbing a single photon and activates multiple copies of the G-protein transducin (G) that trigger further downstream reactions of the phototransduction cascade. The class...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2014.05.050
更新日期:2014-09-02 00:00:00
abstract::Mitochondria often reside in subcellular regions with high metabolic demands. We examined the mechanisms that can govern the relocation of mitochondria to these sites in respiratory neurons. Mitochondria were visualized using tetramethylrhodamineethylester, and their movements were analyzed by applying single-particle...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.106.092981
更新日期:2007-04-15 00:00:00