Recombinant human immune interferon (HuIFN-gamma) was labeled with [gamma-32P]ATP and cyclic-AMP-dependent protein kinase from bovine heart to a specific radioactivity of 11,000 Ci/mmol. At least two molecules of phosphate were incorporated per molecule of interferon. The binding of [32P]HuIFN-gamma to human U937 histiocytic lymphoma cells was time dependent, and displaceable by HuIFN-gamma but...

Polystyrene/poly(acrylic acid) latex particles 0.26 μm in diameter, which were synthesized by emulsion copolymerization of styrene and acrylic acid, were immobilized on the platinum electrode in a uniform film. The film did not block the diffusion current of a ferrocene derivative in the solution. The voltammograms showed the reduction of hydrogen ion, which was supplied not only from the solut...

Frankia strain CcI3 grown in culture produced a hemoglobin which had optical absorption bands typical of a hemoglobin and a molecular mass of 14.1 kDa. Its equilibrium oxygen binding constant was 274 nM, the oxygen dissociation rate constant was 56 s(-1), and the oxygen association rate constant was 206 microM(-1) s(-1).

The mixed dissociation constant of azathioprine—chemically 6-(3-methyl-5-nitroimidazol-4-yl)sulfanyl-7Hpurine at various ionic strengths I of range 0.01-0.2, and at temperatures of 25°C and 37°C, was determined with the use of two different multiwavelength and multivariate treatments of spectral data, SPECFIT32 and SQUAD(84) nonlinear regression analyses and INDICES factor analysis according to...

Protein L consists of a single alpha-helix packed on a four-stranded beta-sheet formed by two symmetrically opposed beta-hairpins. We use a computer-based protein design procedure to stabilize a domain-swapped dimer of protein L in which the second beta-turn straightens and the C-terminal strand inserts into the beta-sheet of the partner. The designed obligate dimer contains three mutations (A5...

a binding study of nickel ions by a new recombinant human growth hormone (hgh), produced as an injected drug, has been done at 27˚c in nacl solution (50 mm) using an isothermal titration calorimetry. there is a set of three identical and non-interacting binding sites for nickel ions. the intrinsic dissociation equilibrium constant and the molar enthalpy of binding are 40 μm and -16.5 kj/mol, re...

The reversible inhibition of acetylcholinesterase (AChE) by 4,4'-bipyridine (BP) was measured with acetylthiocholine as substrate. The enzyme/inhibitor dissociation constant for binding of BP to the catalytic site was Ka = 1.0 mM and the non-competitive dissociation constant for binding to an allosteric site was K, = = 9.0 mM. BP protected AChE against phosphylation by sarin, soman, tabun and V...

The activation of NADHand NADPH-dependent glutamate dehydrogenase-catalyzed reactions appears to be similar for two structurally different compounds, ADP and any of a series of monocarboxylic L-a-amino acids. ADP and L-leucine have identical effects on a large variety of glutamate dehydrogenase-catalyzed reactions. Transient state studies show that L-leucine increases the rate of release of NAD...

G-protein coupled receptors (GPCRs) comprise the largest protein family and mediate the vast majority of signal transduction processes in the body. Until recently GPCRs were not considered to be voltage dependent. Newly it was shown for several GPCRs that the first step in GPCR activation, the binding of agonist to the receptor, is voltage sensitive: Voltage shifts the receptor between two stat...

We report a theoretical investigation of the collision-induced dissociation pyrene dimer cation, as recently investigated in experimental work by Zamith et al. (J. Chem. Phys. 153, 054311 (2020)). Molecular dynamics simulations using potential energies and forces computed at self-consistent charge density functional-based tight binding level were conducted for different collision between 2.5 30...