Abstract:
:Heterogeneity of ADP diffusion and regulation of respiration were studied in permeabilized cardiomyocytes and cardiac fibers in situ and in silico. Regular arrangement of mitochondria in cells was altered by short-time treatment with trypsin and visualized by confocal microscopy. Manipulation of matrix volumes by changing K(+) and sucrose concentrations did not affect the affinity for ADP either in isolated heart mitochondria or in skinned fibers. Pyruvate kinase (PK)-phosphoenolpyruvate (PEP) were used to trap ADP generated in Ca,MgATPase reactions. Inhibition of respiration by PK-PEP increased 2-3 times after disorganization of regular mitochondrial arrangement in cells. ADP produced locally in the mitochondrial creatine kinase reaction was not accessible to PK-PEP in intact permeabilized fibers, but some part of it was released from mitochondria after short proteolysis due to increased permeability of outer mitochondrial membrane. In in silico studies we show by mathematical modeling that these results can be explained by heterogeneity of ADP diffusion due to its restrictions at the outer mitochondrial membrane and in close areas, which is changed after proteolysis. Localized restrictions and heterogeneity of ADP diffusion demonstrate the importance of mitochondrial functional complexes with sarcoplasmic reticulum and myofibrillar structures and creatine kinase in regulation of oxidative phosphorylation.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Saks V,Kuznetsov A,Andrienko T,Usson Y,Appaix F,Guerrero K,Kaambre T,Sikk P,Lemba M,Vendelin Mdoi
10.1016/S0006-3495(03)70065-4subject
Has Abstractpub_date
2003-05-01 00:00:00pages
3436-56issue
5eissn
0006-3495issn
1542-0086pii
S0006-3495(03)70065-4journal_volume
84pub_type
杂志文章abstract::The use of propagation invariant Bessel beams has enabled high-resolution subcellular light sheet fluorescence microscopy. However, the energy within the concentric side lobe structure of Bessel beams increases significantly with propagation length, generating unwanted out-of-focus fluorescence that enforces practical...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2015.05.013
更新日期:2015-06-16 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::We have studied the photoinduced volume changes, energetics, and kinetics in the early steps of the bacteriorhodopsin (BR) photocycle with pulsed, time-resolved photoacoustics. Our data show that there are two volume changes. The fast volume change ( < or = 200 ns) is an expansion (2.5 +/- 0.3 A3/molecule) and is obse...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(96)79235-4
更新日期:1996-07-01 00:00:00
abstract::39K nuclear magnetic resonance (NMR) spectra were readily obtained, in vivo, from rat muscle, kidney, and brain in 5-10 min with signal-to-noise ratios of approximately 20:1. Quantitation of the K+ signal was achieved by reference to an external standard of KCl/dysprosium nitrate as well as by reference to the proton ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(87)83332-5
更新日期:1987-02-01 00:00:00
abstract::Molecular dynamics (MD) simulations of 5 ns on protein-DNA complexes of catabolite-activator protein (CAP), lambda-repressor, and their corresponding uncomplexed protein and DNA, are reported. These cases represent two extremes of DNA bending, with CAP DNA bent severely and the lambda-operator nearly straight when com...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.053843
更新日期:2005-05-01 00:00:00
abstract::Observation of cell membrane buckling and cell folding in micropipette aspiration experiments was used to evaluate the bending rigidity of the red blood cell membrane. The suction pressure required to buckle the membrane surface initially was found to be about one-half to two-thirds of the pressure that caused the cel...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(83)84319-7
更新日期:1983-07-01 00:00:00
abstract::More and more researchers are interested in imaging living (Henderson, 1994) or fixed cells in their natural environment using the atomic force microscope (AFM). However, the AFM tip interacts strongly with the sample, and its z range freedom is limited to a few micrometers. This means that the cells to be imaged have...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)80344-9
更新日期:1995-05-01 00:00:00
abstract::Fluorescence polarization, P, of 1,6-diphenyl-1,3,5-hexatriene was studied in Escherichia coli B/r. Modification of nutritional conditions was not compensated by homeoviscous adaptation, demonstrated to exist for temperature variations. Cell diameter, which is known also to vary with nutrition but not with temperature...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(85)83788-7
更新日期:1985-08-01 00:00:00
abstract::Accommodation may be defined as an increase in the threshold of an excitable membrane when the membrane is subjected to a sustained subthreshold depolarizing stimulus. Some excitable membranes show accommodation in response to currents which rise linearly at a very slow rate. In this report we point out a theoretical ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(80)85059-4
更新日期:1980-08-01 00:00:00
abstract::Molecular dynamics simulations of protein folding and unfolding are often carried out at temperatures (400-600 K) that are much higher than physiological or room temperature to speed up the (un)folding process. Use of such high temperatures changes both the protein and solvent properties considerably, compared to phys...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(00)76820-2
更新日期:2000-06-01 00:00:00
abstract::As normally studied, in the solid state or in solution, poly(beta-benzyl-L-aspartate) (PBLA) differs from the other helical polyamino acids in that its alpha-helical conformation is most stable in the left-handed rather than in the right-handed form. The slightly lower energy per residue for the left-handed form in PB...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(98)77689-1
更新日期:1998-11-01 00:00:00
abstract::By employing classical molecular dynamics, correlation analysis of coupling between slow and fast dynamical modes, and free energy (umbrella) sampling using classical as well as mixed quantum mechanics molecular mechanics force fields, we uncover a possible pathway for phosphoryl transfer in the self-cleaving reaction...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.104661
更新日期:2007-10-01 00:00:00
abstract::Recently a periplasmic glucose/galactose binding protein, GGRQ26C, immobilized on a gold surface has been used as an active part of a glucose biosensor based on quartz microbalance technique. However the nature of the glucose detection was not clear. Here we have found that the receptor protein film immobilized on the...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.060442
更新日期:2006-02-01 00:00:00
abstract::The switch 1 region of myosin forms a lid over the nucleotide phosphates as part of a structure known as the phosphate-tube. The homologous region in kinesin-family motors is more open, not interacting with the nucleotide. We used molecular dynamics (MD) simulations to examine a possible displacement of switch 1 of th...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(01)76092-4
更新日期:2001-03-01 00:00:00
abstract::Mathematical models are increasingly important in biology, and testability is becoming a critical issue. One limitation is that one model simulation tests a parameter set representing one instance of the biological counterpart, whereas biological systems are heterogeneous in their properties and behavior, and a model ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2012.09.034
更新日期:2012-11-07 00:00:00
abstract::A theory based on the Smolukowski analysis of colloid stability shows that the presence of charged, surface-active serum proteins at the alveolar air-liquid interface can severely reduce or eliminate the adsorption of lung surfactant from the subphase to the interface, consistent with the observations reported in the ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.062646
更新日期:2005-09-01 00:00:00
abstract::We elucidate the physics of protein dynamical transition via 10-100-ns molecular dynamics simulations at temperatures spanning 160-300 K. By tracking the energy fluctuations, we show that the protein dynamical transition is marked by a crossover from nonstationary to stationary processes that underlie the dynamics of ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2009.07.036
更新日期:2009-10-07 00:00:00
abstract::The lateral mobility of pyrenyl phospholipid probes in dimyristoylphosphatidylcholine (DMPC) vesicles was determined from the dependence of the pyrene monomeric and excimeric fluorescence yields on the molar probe ratio. The analysis of the experimental data makes use of the milling crowd model for two-dimensional dif...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(90)82530-3
更新日期:1990-02-01 00:00:00
abstract::The E5 oncoprotein is the major transforming protein of bovine papillomavirus type 1. This 44-residue transmembrane protein can interact with the platelet-derived growth factor receptor β, leading to ligand-independent activation and cell transformation. For productive interaction, E5 needs to dimerize via a C-termina...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2010.06.073
更新日期:2010-09-22 00:00:00
abstract::It was shown previously that a significant fraction of the myosin crossbridges is attached to actin in the skinned rabbit psoas fibers under relaxed conditions at low ionic strength and low temperature (Brenner, B., M. Schoenberg, J. M. Chalovich, L. E. Greene, and E. Eisenberg. 1982. Proc. Natl. Acad. Sci. USA. 79:72...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(89)82838-3
更新日期:1989-03-01 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
pub_type: 杂志文章
doi:10.1016/S0006-3495(88)82944-8
更新日期:1988-07-01 00:00:00
abstract::Myosin II is a central mechanoenzyme in a wide range of cellular morphogenic processes. Its cellular localization is dependent not only on signal transduction pathways, but also on mechanical stress. We suggest that this stress-dependent distribution is the result of both the force-dependent binding to actin filaments...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2011.12.020
更新日期:2012-01-18 00:00:00
abstract::To record post synaptic potentials or electrical activity from processes of single cells in a central nervous system (CNS) preparation in situ, voltage sensitive dyes can be injected intracellularly, thereby staining only the cell under investigation. We report the structure, evaluation, and synthesis of 11 fluorescen...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(87)83389-1
更新日期:1987-04-01 00:00:00
abstract::The M2 protein from the influenza A virus forms a proton channel in the virion that is essential for infection. This tetrameric protein appears to form a four-helix bundle spanning the viral membrane. Here the solid-state NMR method, 2D polarization inversion spin exchange at magic angle (PISEMA), has been used to obt...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(00)76334-X
更新日期:2000-08-01 00:00:00
abstract::Stress fibers are cellular contractile actomyosin machines central to wound healing, shear stress response, and other processes. Contraction mechanisms have been difficult to establish because stress fibers in cultured cells typically exert isometric tension and present little kinetic activity. In a recent study, livi...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2009.04.051
更新日期:2009-07-22 00:00:00
abstract::A detailed picture of water and ion properties in small pores is important for understanding the behavior of biological ion channels. Several recent modeling studies have shown that small, hydrophobic pores exclude water and ions even if they are physically large enough to accommodate them, a mechanism called hydropho...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.080432
更新日期:2006-05-15 00:00:00
abstract::The p7 protein from hepatitis C virus is critical for the assembly and secretion of infectious virus, making it an attractive drug target. It is thought to be a viroporin with a demonstrated ion channel activity when reconstituted into planar lipid bilayers. Electron microscopy experiments suggest that p7 oligomers co...
journal_title:Biophysical journal
pub_type: 信件
doi:10.1016/j.bpj.2008.10.004
更新日期:2009-01-01 00:00:00
abstract::Using a recently developed in vitro motility assay, we have demonstrated that local anesthetics directly inhibit myosin-based movement of single actin filaments in a reversible dose-dependent manner. This is the first reported account of the actions of local anesthetics on purified proteins at the molecular level. In ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(96)79466-3
更新日期:1996-11-01 00:00:00
abstract::A new method for the investigation of ion translocating membrane proteins is presented. Protein containing membrane fragments or vesicles are adsorbed to a solid supported membrane. The solid supported membrane consists of a lipid monolayer on a gold evaporated or gold sputtered glass substrate which is coated with a ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(93)81379-1
更新日期:1993-02-01 00:00:00
abstract::The molecular motion of retinal within the purple membrane was investigated by flash-induced absorption anisotropies with or without ethanol. In the absence of ethanol, the measured anisotropies at several wavelengths exhibited almost the same slow decay. This slow decay was attributed to only the rotation of purple m...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(97)78076-7
更新日期:1997-07-01 00:00:00