Abstract:
:Well-ordered multilamellar arrays of liquid-crystalline phosphatidylcholine and equimolar phosphatidylcholine-cholesterol bilayers have been formed in the nonaqueous solvents formamide and 1,3-propanediol. The organization of these bilayers and the interactions between apposing bilayer surfaces have been investigated by X-ray diffraction analysis of liposomes compressed by applied osmotic pressures up to 6 X 10(7) dyn/cm2 (60 atm). The structure of egg phosphatidylcholine (EPC) bilayers in these solvents is quite different than in water, with the bilayer thickness being largest in water, 3 A narrower in formamide, and 6 A narrower in 1,3-propanediol. The incorporation of equimolar cholesterol increases the thickness of EPC bilayers immersed in each solvent, by over 10 A in the case of 1,3-propanediol. The osmotic pressures of various concentrations of the neutral polymer poly(vinylpyrrolidone) dissolved in formamide or 1,3-propanediol have been measured with a custom-built membrane osmometer. These measurements are used to obtain the distance dependence of the repulsive solvation pressure between apposing bilayer surfaces. For each solvent, the solvation pressure decreases exponentially with distance between bilayer surfaces. However, for both EPC and EPC-cholesterol bilayers, the decay length and magnitude of this repulsive pressure strongly depend on the solvent. The decay length for EPC bilayers in water, formamide, and 1,3-propanediol is found to be 1.7, 2.4, and 2.6 A, respectively, whereas the decay length for equimolar EPC-cholesterol bilayers in water, formamide, and 1,3-propanediol is found to be 2.1, 2.9, and 3.1 A, respectively. These data indicate that the decay length is inversely proportional to the cube root of the number of solvent molecules per unit volume.(ABSTRACT TRUNCATED AT 250 WORDS)
journal_name
Biochemistryjournal_title
Biochemistryauthors
McIntosh TJ,Magid AD,Simon SAdoi
10.1021/bi00445a053subject
Has Abstractpub_date
1989-09-19 00:00:00pages
7904-12issue
19eissn
0006-2960issn
1520-4995journal_volume
28pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract::The enzyme thymidylate synthase (TS) catalyzes a complex reaction that involves forming and breaking at least six covalent bonds. The physical nature of the hydride transfer step in this complex reaction cascade has been studied by means of isotope effects and their temperature dependence. Competitive kinetic isotope ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi036124g
更新日期:2004-02-24 00:00:00
abstract::Two forms of cytochrome P-450, designated P-450NMa and P-450NMb, were purified to electrophoretic homogeneity from rabbit nasal microsomes. The purified cytochromes, which contained 14-16 nmol of P-450/mg of protein, exhibited apparent monomeric molecular weights of 49,500 and 51,000, respectively. As indicated by sev...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00422a007
更新日期:1988-11-01 00:00:00
abstract::One of the arguments in favor of the protein-only hypothesis of transmissible spongiform encephalopathies is the link between inherited prion diseases and specific mutations in the PRNP gene. One such mutation (Asp178 --> Asn) is associated with two distinct disorders: fatal familial insomnia or familial Creutzfeldt-J...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi051455+
更新日期:2005-12-06 00:00:00
abstract::Peptide mapping, chemical sequencing, microbore HPLC/electrospray ionization mass spectrometry (LC/ESI/MS), and matrix-assisted laser desorption mass spectrometry (MALDI/MS) were used to identify the sites of intra- and intermolecular disulfide linkages in bovine dopamine beta-hydroxylase. The enzyme contains 14 cyste...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00204a019
更新日期:1994-09-27 00:00:00
abstract::The structure of a mutant Escherichia coli thioredoxin with a glutamic acid substituted for a conserved lysine at position 36 adjacent to the active site has been solved using molecular replacement and refined at 2.0-A resolution to a crystallographic residual of 19.9%. The mutant was crystallized in an orthorhombic s...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00070a017
更新日期:1993-05-18 00:00:00
abstract::Structural changes during the photochemical reactions of unhydrated air-dried films of bovine rhodopsin in rod outer segments were examined by visible and Fourier transform infrared (FTIR) spectroscopy at 200, 240, and 280 K. These films exhibited conversion from a lumirhodopsin state to a metarhodopsin I state with a...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00051a025
更新日期:1995-12-26 00:00:00
abstract::The complete coordination scheme for Mn(II) in transition-state-analogue complexes with creatine kinase has been determined by electron paramagnetic resonance (EPR) spectroscopy. Perturbations in the EPR spectra for Mn(II) due to superhyperfine coupling to 17O of selectively labeled ligands have been used to identify ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00565a002
更新日期:1980-11-25 00:00:00
abstract::Epitranscriptomic RNA modifications can serve as recognition elements for the recruitment of effector proteins (i.e., "readers") to modified transcripts. While these interactions play an important role in mRNA regulation, there is a major gap in our understanding of the sequence determinants critical for the binding o...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.9b00485
更新日期:2019-08-06 00:00:00
abstract::The solution conformation is presented for representatives of each of the major classes of asparaginyl oligosaccharides. In this report the conformation of alpha(1-3)-, alpha(1-2)-, beta(1-2)-, and beta(1-4)-linked units is described. The conformational properties of these glycopeptides were determined by high-resolut...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00284a021
更新日期:1983-07-19 00:00:00
abstract::High-resolution 2D NMR spectra of the duplex CGCGAATTCGCG with deoxyribose sugars but with the normal phosphodiester linker replaced by an N3' --> P5' phosphoramidate (NP) group have been used to establish a solution structure for the duplex. Distance, angle, and base pair hydrogen-bonding constraints were used to ref...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi980711y
更新日期:1998-09-01 00:00:00
abstract::Cytochrome P450 BM-3 is a bacterial enzyme with sequence similarity to mammalian P450s that catalyzes the hydroxylation of fatty acids with high efficiency. Enzyme-substrate binding and dynamics has been an important topic of study for cytochromes P450 because most of the crystal structures of substrate-bound structur...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi4000645
更新日期:2013-10-01 00:00:00
abstract::Lactose repressor protein, regulator of lac enzyme expression in Escherichia coli, maintains its structure and function at extremely low protein concentrations (<10(-)12 M). To examine the unfolding and dissociation of this tetrameric protein, structural transitions in the presence of varying concentrations of urea we...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9900727
更新日期:1999-05-18 00:00:00
abstract::N-RAP is a recently discovered muscle-specific protein found at cardiac intercalated disks. Double immunogold labeling of mouse cardiac muscle reveals that vinculin is located immediately adjacent to the fascia adherens region of the intercalated disk membrane, while N-RAP extends approximately 100 nm further toward t...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0107445
更新日期:2001-12-11 00:00:00
abstract::Two-dimensional (2D) proton magnetic resonance techniques used in conjunction with laser photochemically induced dynamic nuclear polarization (photo-CIDNP) spectroscopy have been applied to studying the kringle 4 domain from human plasminogen at 360 MHz. Out of 11 potential CIDNP-sensitive aromatic side chains, only 5...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00372a020
更新日期:1986-12-02 00:00:00
abstract::A study of the dynamics and mechanism of the various thermotropic phase transitions undergone by the hydrated monoacylglycerides monoolein and monoelaidin, in the temperature range of 20-120 degrees C and from 0 to 5 M NaCl, has been undertaken. Measurements were made by using time-resolved X-ray diffraction at the Co...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00394a008
更新日期:1987-10-06 00:00:00
abstract::The conformation of the trans-anti-(1S,2R,3S,4R)-N(2)-[1-(1,2,3,4-tetrahydro-2,3,4-trihydroxybenz[a]anthracenyl)]-2'-deoxyguanosyl adduct in d(G(1)G(2)C(3)A(4)G(5)X(6)T(7)G(8)G(9)T(10)G(11)).d(C(12)A(13)C(14)C(15)A(16)C(17)C(18)T(19)G(20)C(21)C(22)), bearing codon 12 of the human N-ras protooncogene (underlined), was ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi020462k
更新日期:2003-03-04 00:00:00
abstract::Little is known about the extent to which protein flexibility contributes to antigen-antibody recognition and cross-reactivity. Using short coil peptides (leucine zippers) as model antigens, we demonstrate that a monoclonal antibody can force a noncognate peptide into a conformation that is similar to the conformation...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00050a035
更新日期:1995-12-19 00:00:00
abstract::The exopeptidases dipeptidyl aminopeptidases I and IV were used to hydrolyze the N-terminal portion of spinach plastocyanin to dipeptides. The enzymes were used individually as well as in a mixture and the dipeptides were analyzed by combined gas chromatography-mass spectrometry. Data are presented for native plastocy...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00596a009
更新日期:1978-02-07 00:00:00
abstract::Nickel is a fundamental micronutrient for cellular life, but it is toxic in soluble form at nonphysiological concentrations. Such potentially contradictory features required living organisms to develop efficient systems for nickel utilization and homeostasis. This is the case for incorporation of nickel into the activ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi6024676
更新日期:2007-03-20 00:00:00
abstract::The tau microtubule-associated proteins are axonal proteins that have been implicated in axonal outgrowth, microtubule spacing, and microtubule bundling. Moreover, tau is the major structural component of the paired helical filaments present in the brains of Alzheimer's disease patients. The Caenorhabditis elegans Gen...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi952646n
更新日期:1996-07-23 00:00:00
abstract::A heparin-induced conformational change is required to convert antithrombin from a slow to a fast inhibitor of factor Xa. It has been proposed [van Boeckel et al. (1994) Nat. Struct. Biol. 1, 423-425] that the reactive center residue P14 is inserted into beta-sheet A in native antithrombin and is displaced from the be...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9604643
更新日期:1996-07-02 00:00:00
abstract::The transfer of ganglioside GM1 from micelles to membranes and between different membrane populations has been examined by using a pyrene fatty acid derivative of the ganglioside. The transfer of gangliosides from micelles to membranes depends on the physical state as well as the molecular composition of the acceptor ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00375a032
更新日期:1987-01-13 00:00:00
abstract::The enzyme hydrogenase, from the photosynthetic bacterium Chromatium, was purified to homogeneity after solubilization of the particulate enzyme with deoxycholate. The purification procedure included ammonium sulfate fractionation, treatment with manganous phosphate gel, heating at 63 degrees, DEAE-cellulose chromatog...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00683a001
更新日期:1975-06-17 00:00:00
abstract::Perioperative bleeding is a cause of major blood loss and is associated with increased rates of postoperative morbidity and mortality. To combat this, antifibrinolytic inhibitors of the serine protease plasmin are commonly used to reduce bleeding during surgery. The most effective and previously widely used of these i...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi201203y
更新日期:2011-10-04 00:00:00
abstract::Piscidin 1 (Pis-1) is a novel cytotoxic peptide with a cationic alpha-helical structure that was isolated from the mast cells of hybrid striped bass [Silphaduang, U., and Noga, E. J. (2001) Nature 414, 268-269]. Pis-1 is not selective for bacterial versus mammalian cells. In the present study, to develop novel antibio...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi062233u
更新日期:2007-03-27 00:00:00
abstract::We consider the problem of color regulation in visual pigments for both bovine rhodopsin (lambda max = 500 nm) and octopus rhodopsin (lambda max = 475 nm). Both pigments have 11-cis-retinal (lambda max = 379 nm, in ethanol) as their chromophore. These rhodopsins were bleached in their native membranes, and the opsins ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00432a055
更新日期:1989-03-21 00:00:00
abstract::Pancreatic phospholipase A(2) (PLA2) shows a strong preference for the binding to the anionic interface and a consequent allosteric activation. In this paper, we show that virtually all the preference is mediated through 3 (Lys-53, -56, and -120) of the 12 cationic residues of bovine pancreatic PLA2. The lysine-to-met...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi000740k
更新日期:2000-10-10 00:00:00
abstract::The interaction of nile red (NR) with apomyoglobin (ApoMb) in the native (pH 7) and molten globule (pH 4) states was investigated using experimental and computational methods. NR binds to hydrophobic locations in ApoMb with higher affinity (K(d) = 25 +/- 5 microM) in the native state than in the molten globule state (...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi051905y
更新日期:2006-04-25 00:00:00
abstract::The kinetic parameters (kpol, Kd app) for all possible correct and incorrect pairing between the A, T, G, and C bases were determined for wild-type (WT) rat DNA polymerase beta (pol beta) and the R283A mutant under pre-steady-state kinetic assay conditions. The base substitution fidelities of these two proteins were t...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi961653o
更新日期:1997-02-04 00:00:00
abstract::The fibrillation of misfolded neurodegenerative disease-related proteins has been extensively studied over the past few decades, but the initial oligomerization has been rarely examined even though some recent evidence indicated that small protein oligomers are more neurotoxic than long protein fibers. It is rather di...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.7b00966
更新日期:2017-12-19 00:00:00