Showing papers in "Biophysical Chemistry in 1977"

TL;DR: Here the theory is extended in a simple manner to finite concentrations, and the stability of the charge fraction is found to be firmly based on consequences of the long-range polyelectrolyte field.

TL;DR: The translational diffusion of the amphiphilic molecules in a number of lyotropic liquid crystalline phases has been measured with the pulsed NMR pulsed magnetic field gradient method and it was found that the difussion coefficient depend markedly on the Amphiphile end group in a way that parallels the area per polar head group as determined in X-ray studies.

TL;DR: It is shown that the colloidal instability of chymosin-treated casein micelles cannot be explained on the basis of the well-known theory of the stability of lyophobic colloids, but that clotting is achieved through short-range interactions.

TL;DR: There was no parallel relation between the lifetime and quantum yield for proflavine; the lifetime showed a minimum around P/D equals 10 and the quantum yield of acridine orange increased in a parallel fashion with increasing P/ D ratio.

TL;DR: The present work extends a previous work by treating the chains more generally as coiled instead of straight, and applying the "sliding" model to the lac repressor-operator association.

TL;DR: In an isothermal continuously stirred tank reactor fed by sulphuric acid solutions of bromate, bromide and cerium (III) bistability is experimentally observed, which has important consequences for the understanding of excitability and biochemical control mechanisms.

TL;DR: No statistical evidence could be produced for the widely held belief that the clotting time should be inversely proportional to the enzyme concentration, but varying exponents of the latter in its relation to the clotts time are discussed in terms of von Smoluchowski's theory of the slow coagulation of colloidal particles.

TL;DR: These results represent the first direct determination of this important parameter for a ribo-oligonucleotide and are considerably lower than any of the previously published van't Hoff enthalpies but is consistent with values that can be derived from other calorimetric data.

TL;DR: The calculations reveal that rapidly reversible, ampholyte-induced macromolecular isomerization can give well resolved, bimodal transient and equilibrium isoelectric focusing patterns in which the two peaks correspond to different chemical equilibrium compositions and not to separated isomers.

TL;DR: The theory is extended to include small molecules which bind to the protein molecule and affect the structural state and the changes of structural state caused by specific and non-specific binding and allosteric effects are explained in a unified manner.

TL;DR: The large positive entropy change accompanying the interaction appears to be due to extensive release of water from the DNA and daunomycin, although the apparent association constant remained largely unaffected by ionic strength.

TL;DR: For high affinity systems and favorable energy distributions, it is found that the errors in estimated binding free energies may be less than one kcal provided the measurement errors are strictly random and of small magnitude.

TL;DR: The Darcy constant for permeation can be calculated from data at the frequency where the apparent storage and loss shear moduli are equal, without the necessity of measurements at much lower frequencies as previously employed.

TL;DR: The statistical thermodynamic model of protein structure proposed in paper I is developed with special attention to the hydrophobic interaction, and measurements of the thermal denaturation of five globular proteins, ribonuclease A, lysozyme, alpha-chymotrypsin, cytochrome c, and myoglobin, are quantitatively analyzed using the model.

TL;DR: Two methods have been developed for the analysis of four types of indefinite self-associations and it was found that one could indeed distinguish between the four types.

TL;DR: A simple theoretical equation for the binding of Mg2+ to DNA in the presence of excess 1:1 salt is derived from a model that does not specify discrete binding sites but rather allows the associated metal ions to move freely near the surface of the DNA polyion.

TL;DR: The threshold effect found experimentally by Pörschke, and particularly the observed linear dependence of the threshold field on the logarithm of the ionic strength, appears here as a simple consequence of the linear increase of the stabilization free energy with the logarym of Ionic strength.

TL;DR: Transient and equilibrium isoelectric focusing patterns have been computed for pH-dependent conformational transitions in the limits of complete cooperativity and instantaneous chemical equilibration.

TL;DR: The data for the macrotetrolides indicate the existence of conformational transition prior to complexation, and a sequential substitution or “redressing” mechanism is proposed which is in accord with the high rates of complex formation.

TL;DR: The fluorescence intensity of the single tyrosine residue in histone H1 increases from R TYR = 0.3 to RTYR = 1.3 as the protein undergoes a conformational change from the random coil state to a folded form.

TL;DR: It appears that there is no need to invoke more than one class of binding sites on tRNA's, meaning that the experimental binding data can be described using the same intrinsic pK value for all phosphate groups.

TL;DR: The kinetic data reported here for 1 M NaCl is compared with previously published results obtained at lower salt concentrations and is discussed in terms of the quantitative effect of ionic strength on the kinetics of helix-coil transitions in oligo- and polynucleotides.

TL;DR: Its solution (in the case of the DNA double-helix in B-form) shows that the DNA backbone can form a coiled-coil with parameters close to those estimated from experimental data on DNP in chromatine from nuclei of cells.

TL;DR: Solution of chlorophyll a in liquid crystals mixture (MBBA + EBBA) was investigated and the interaction between the pigment and solvent exceeds pigment-pigment interaction because the solvent appears to have a stronger influence on the Chl spectrum.

TL;DR: To relate the volume Changes of the over-all process to those of the intermediate complexes, the partial molal volume of ethanol, acetaldehyde, NAD + and NADH are determined by density measuraments and it is found that the Dissociation of binary complexes is followed by large volume decreases, while the dissociation of ternary complexes is follow by smaller volume increases.

TL;DR: This contribution contains a personal account of the early days of polyelectrolyte research, a discussion of the configurational properties of poly Electrolyte chains, a brief review of polyetectrolytes theories and some remarks concerning recent experimental and theoretical developments as well as future trends.

TL;DR: Correlation of these three measurements demonstrated that nucleotide splitting and exchange were mainly connected with the association and dissociation reactions of actin protomers at the ends ofActin filaments and were not caused by release and rebinding of nucleotide molecules at the binding sites along the filament.

TL;DR: Findings have been interpreted as follows that samples isolated as 70S tight couples from sucrose gradients at 5 mM Mg 2+ spontaneously revert within hours into micro-heterogeneous material containing about 15% loose couples, for both types of ribosomes.

TL;DR: It was found that the velocity of thermoosmosis is proportional to the effective temperature difference and the proprtionality constant (themosmotic coefficient) is a function of electrolyte concentration.

TL;DR: The average conformation of GpU and UpG in neutral aqueous solutions has been investigated by proton chemical shifts and coupling measurements as well as T1 relaxation time experiments to provide information about the syn--anti equilibrium of the orientation of the base about the glycosidic bond.