Disulfide bond cleavage of human serum albumin and alterations of its secondary structure by cis-diamminedichloroplatinum(II)

Human serum albumin (HSA) is the most abundant protein in blood plasma. HSA is involved in the transport of hormones, fatty acids, and some other compounds, maintenance of blood pH, osmotic pressure, and many other functions. Although this protein is well studied, data about its conformational changes upon different denaturation factors are fragmentary and sometimes contradictory. This is especially true for FTIR spectroscopy data interpretation. Here, the effect of various denaturing agents on the structural state of HSA by using FTIR spectroscopy in the aqueous solutions was systematically studied. Our data suggest that the second derivative deconvolution method provides the most consistent interpretation of the obtained IR spectra. The secondary structure changes of HSA were studied depending on the concentration of the denaturing agent during acid, alkaline, and thermal denaturation. In general, the denaturation of HSA in different conditions is accompanied by a decrease in α-helical conformation and an increase in random coil conformation and the intermolecular β-strands. Meantime, some variation in the conformational changes depending on the type of the denaturation agent were also observed. The increase of β-structural conformation suggests that HSA may form amyloid-like aggregates upon the denaturation.

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Interaction of the Fungicide Tebuconazole with Human Serum Albumin: A Preliminary Study

Folia Veterinaria ◽

10.2478/fv-2018-0020 ◽

2018 ◽

Vol 62 (2) ◽

pp. 85-91 ◽

Cited By ~ 1

Author(s):

J. Staničová ◽

K. Želonková ◽

V. Verebová ◽

B. Holečková ◽

J. Dianovský

Keyword(s):

Secondary Structure ◽

Human Serum Albumin ◽

Fluorescence Quenching ◽

Serum Albumin ◽

Human Serum ◽

Binding Sites ◽

Triazole Fungicides ◽

Number Of Binding Sites ◽

Preliminary Study ◽

Protein Macromolecule

Abstract The interactions between the fungicide tebuconazole and human serum albumin were investigated using fluorescence and circular dichroism spectroscopies. The experimental results showed that the fluorescence quenching of the protein by the tebuconazole molecule was a result of the formation of a ligand-protein complex with a binding constant of 8.51×103 l.mol−1 and the number of binding sites in the macromolecule was close to 1. These findings demonstrated the fact that although the binding affinity of tebuconazole to the protein may be slight, it was very similar to other triazole fungicides. In addition, tebuconazole stabilized the α-helical secondary structure of the human serum albumin due to the increase of the α-content in the protein macromolecule.

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Steric accessibility of tyrosine residues in human serum albumin

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19791657 ◽

1979 ◽

Vol 44 (5) ◽

pp. 1657-1670 ◽

Cited By ~ 13

Author(s):

Ladislav Morávek ◽

Mohamed Ali Saber ◽

Bedřich Meloun

Keyword(s):

Amino Acid ◽

Secondary Structure ◽

Human Serum Albumin ◽

Serum Albumin ◽

Human Serum ◽

Amino Acid Analysis ◽

Cyanogen Bromide ◽

Tyrosine Residues ◽

Steric Accessibility ◽

The Individual

Human serum albumin was nitrated by an excess of tetranitromethane at pH 8.0. As shown by amino acid analysis, of the 18 tyrosine residues present in albumin about 7-7.5 residues remain unaltered, 9 residues are converted into 3-nitrotyrosine, and 1.2 residue into 3,5-dinitrotyrosine. The nitrated albumin was digested with cyanogen bromide to three fragments which comprise the whole original molecule. The individual fragments were converted into their S-sulfo derivatives and the latter digested with chymotrypsin or stepwise with trypsin and thermolysin. The yellow, nitrotyrosine-containing peptides were isolated from the digest and the positions of nitrated tyrosine residues in albumin thus located. Residues No 30, 148, 150, 161, 334, 341, 401, and 411 were identified as strongly nitrated and residues No 84, 138, 452, and 497 as medium nitrated. Residues No 140, 263, 319, 332, 353, and 367 either react weakly or were not found in nitrated form. Residue No 411 and partly also 161 were converted into 3,5-dinitrotyrosine. The accessibility of the individual tyrosine residues to the nitrating agent is discussed with respect to their positions in disulfide loops and hypothetic parts of the secondary structure of albumin.

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Effect of ketoprofen-based ionic liquids on secondary structure and thermal stability of human serum albumin

Journal of Thermal Analysis and Calorimetry ◽

10.1007/s10973-020-10111-4 ◽

2020 ◽

Vol 142 (5) ◽

pp. 1911-1917

Author(s):

Proletina Kardaleva ◽

Maya Guncheva ◽

Svetla Todinova ◽

Ivan Angelov ◽

Paula Ossowicz ◽

...

Keyword(s):

Thermal Stability ◽

Ionic Liquids ◽

Secondary Structure ◽

Human Serum Albumin ◽

Serum Albumin ◽

Human Serum ◽

Thermal Stability Of

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Crosslinking of human plasma C-reactive protein to human serum albumin via disulfide bond oxidation

Redox Biology ◽

10.1016/j.redox.2021.101925 ◽

2021 ◽

Vol 41 ◽

pp. 101925

Author(s):

Shuwen Jiang ◽

Per Hägglund ◽

Luke Carroll ◽

Lars M. Rasmussen ◽

Michael J. Davies

Keyword(s):

Human Serum Albumin ◽

Serum Albumin ◽

Human Serum ◽

Human Plasma ◽

Disulfide Bond ◽

C Reactive Protein ◽

Reactive Protein

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Influence of mutations caused by radiation exposure on the bilirubin binding sites of human serum albumin

Proceedings of the National Academy of Sciences of Belarus Medical series ◽

10.29235/1814-6023-2021-18-1-46-57 ◽

2021 ◽

Vol 18 (1) ◽

pp. 46-57

Author(s):

V. V. Poboinev ◽

V. V. Khrustalev ◽

A. N. Stojarov ◽

T. A. Khrustaleva

Keyword(s):

Amino Acid ◽

Secondary Structure ◽

Human Serum Albumin ◽

Serum Albumin ◽

Radiation Exposure ◽

Human Serum ◽

Binding Sites ◽

Amino Acid Substitutions ◽

Amino Acid Residues ◽

Bilirubin Binding

In this article we analyze the bilirubin binding sites of human serum albumin from the point of view of the secondary structure instability, as well as the effect of amino acid substitutions caused by radiation exposure on the ability of albumin to bind bilirubin-IX-alpha. Based on calculations of binding energy and inhibition constants of bilirubin-albumin complexes before and after the amino acid substitutions, it was found that amino acid substitutions have different effects on the ability of human serum albumin to bind bilirubin. Amino acid substitutions Asp269-Gly269 (Nagasaki-1), Glu354-Lys354 (Hiroshima-1), Asp375-Asn375 (Nagasaki-2) reduce the binding free energy of bilirubin with human serum albumin, and the amino acid substitutions His3-Gln3 (Nagasaki-3) and Glu382-Lys382 (Hiroshima-2) increase it during molecular docking with the corresponding areas of the protein surface. The inhibition constants are significantly higher than with known binding sites. In general, mutations caused by radiation exposure cannot effect on bilirubin binding sites of human serum albumin, since the amino acid residues that are replaced do not interact with the amino acid residues from the binding sites (Leu115, Arg117, Phe134, Tyr138, Ile142, Phe149, Phe157, Tyr161, Arg186, Lys190, Lys240, Arg222). All amino acid residues from known binding sites are located in stable elements of the secondary structure of human serum albumin.The data obtained are important for understanding the impact of radiation exposure on the development of bilirubin encephalopathy in the population of the Chernobyl region and Japan.

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