Kinetic studies of the reactions of benzo[a]pyrene-7,8-diol 9,10-epoxides in aqueous solutions of human serum albumin and nonionic micelles

The Cu(II)-exchange reactions of L-histidine with human serum albumin and diglycyl-L-histidine were studied at pH 7.53 in 0.1 MN-ethylmorpholine–HCl buffer. The exchange rates from L-histidine to albumin and peptide were determined as 0.67 and 0.42 s−1 respectively. Those from albumin and peptide to L-histidine were obtained as 0.04 and 0.07 s−1 respectively. This result is in accord with the earlier observations of the equilibrium study that the peptide has about half the Cu(II)-binding affinity as compared to albumin. The difference in the Cu(II)-exchange rates of albumin and peptide may reflect the influence of either the COOH-terminal free carboxyl group of the peptide or the side-chain residues of the Cu(II)-binding site in the native protein or both. An exchange mechanism is proposed in which the ternary complexes are shown to play the important role in the rate-determining step in the Cu(II)-exchange between a macromolecule and a small substance.

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Chiral Separation Mechanisms in Protein-Based HPLC Columns. 2. Kinetic Studies of (R)- and (S)-Warfarin Binding to Immobilized Human Serum Albumin

Analytical Chemistry ◽

10.1021/ac950827p ◽

1996 ◽

Vol 68 (7) ◽

pp. 1218-1225 ◽

Cited By ~ 71

Author(s):

Bounthon Loun ◽

David S. Hage

Keyword(s):

Human Serum Albumin ◽

Serum Albumin ◽

Human Serum ◽

Chiral Separation ◽

Kinetic Studies ◽

Separation Mechanisms

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Calculation of the Effective Macromolecular Radii of Human Serum Albumin from the Shear Viscosity Data for Its Aqueous Solutions

Ukrainian Journal of Physics ◽

10.15407/ujpe64.4.287 ◽

2019 ◽

Vol 64 (4) ◽

pp. 287 ◽

Cited By ~ 5

Author(s):

O. V. Khorolskyi

Keyword(s):

Human Serum Albumin ◽

Serum Albumin ◽

Aqueous Solutions ◽

Human Serum ◽

Shear Viscosity ◽

Effective Radius ◽

Water Molecules ◽

Viscosity Data ◽

Molecular Radius

The Malomuzh–Orlov theory is used to analyze the experimental shear viscosity data obtained for aqueous solutions of human serum albumin (HSA) at pH = 7.0 in wide temperature and concentration intervals, which allowed the effective radii of HSA macromolecules to be calculated. It is shown that three intervals of the effective molecular radius of HSA with different behaviors can be distinguished in a temperature interval of 278–318 K: 1) below the crossover concentration, the effective molecular radius of HSA remains constant; 2) in the interval from the crossover concentration to about 10 wt%, the effective molecular radius of HSA in the aqueous solution nonlinearly decreases; and 3) at concentrations of 10.2–23.8 wt%, the effective radius of HSA macromolecules linearly decreases, as the concentration grows. The assumption is made that the properties of water molecules in the solution bulk play a crucial role in the dynamics of HSA macromolecules at the vital concentrations of HSA in the solutions. The role of water near the surface of HSA macromolecules and the corresponding changes of its physical properties have been discussed.

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