Determining the binding affinity and binding site of bensulfuron-methyl to human serum albumin by quenching of the intrinsic tryptophan fluorescence

The pharmacological properties of any drug are related to its ability to interact with macromolecular blood components. The interaction of human serum albumin (HSA) and apotransferrin (ATf) with six RuII complexes containing ketoconazole (KTZ), which we have previously reported to be active against Leishmania major and Trypanosoma cruzi, has been investigated by monitoring the tryptophan fluorescence intensity of each protein upon incremental addition of the complexes. All the Ru-KTZ derivatives, namely cis-fac-[RuIICl2(DMSO)3(KTZ)] (1), cis-[RuIICl2(bipy)(DMSO)(KTZ)] (2), [RuII(η6-p-cymene)Cl2(KTZ)] (3), [RuII(η6-p-cymene)(en)(KTZ)][BF4]2 (4), [RuII(η6-p-cymene)(bipy)(KTZ)][BF4]2 (5), and [RuII(η6-p-cymene)(acac)(KTZ)][BF4] (6) are able to quench the intrinsic fluorescence of HSA and ATf at 27 ºC. Analysis of the spectroscopic data using Stern-Volmer plots indicates that in both cases the quenching takes place principally through a static mechanism involving the formation of Ru complex-protein adducts; further analysis of the fluorescence data allowed the estimation of apparent association constants and the number of binding sites for each protein and each compound. The results indicate that both HSA and ATf are possible effective transporters for Ru-KTZ antiparasitic drugs.

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Interaction of coomassie brilliant blue G250 with human serum albumin: Probing of the binding mechanism and binding site by spectroscopic and molecular modeling methods

Journal of Molecular Structure ◽

10.1016/j.molstruc.2010.01.015 ◽

2010 ◽

Vol 968 (1-3) ◽

pp. 24-31 ◽

Cited By ~ 29

Author(s):

Yue-Sheng Li ◽

Yu-Shu Ge ◽

Yue Zhang ◽

Ai-Qing Zhang ◽

Shao-Fa Sun ◽

...

Keyword(s):

Molecular Modeling ◽

Human Serum Albumin ◽

Serum Albumin ◽

Human Serum ◽

Binding Site ◽

Brilliant Blue ◽

Binding Mechanism ◽

Coomassie Brilliant Blue ◽

Modeling Methods ◽

Coomassie Brilliant

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Indomethacin Increases Quercetin Affinity for Human Serum Albumin: A Combined Experimental and Computational Study and Its Broader Implications

International Journal of Molecular Sciences ◽

10.3390/ijms21165740 ◽

2020 ◽

Vol 21 (16) ◽

pp. 5740

Author(s):

Hrvoje Rimac ◽

Tana Tandarić ◽

Robert Vianello ◽

Mirza Bojić

Keyword(s):

Human Serum Albumin ◽

Serum Albumin ◽

Human Serum ◽

Binding Site ◽

Binding Sites ◽

Quantum Chemical ◽

Computational Study ◽

The Body ◽

Active Concentration ◽

Insight Into

Human serum albumin (HSA) is the most abundant carrier protein in the human body. Competition for the same binding site between different ligands can lead to an increased active concentration or a faster elimination of one or both ligands. Indomethacin and quercetin both bind to the binding site located in the IIA subdomain. To determine the nature of the HSA-indomethacin-quercetin interactions, spectrofluorometric, docking, molecular dynamics studies, and quantum chemical calculations were performed. The results show that the indomethacin and quercetin binding sites do not overlap. Moreover, the presence of quercetin does not influence the binding constant and position of indomethacin in the pocket. However, binding of quercetin is much more favorable in the presence of indomethacin, with its position and interactions with HSA significantly changed. These results provide a new insight into drug-drug interactions, which can be important in situations when displacement from HSA or other proteins is undesirable or even desirable. This principle could also be used to deliberately prolong or shorten the xenobiotics’ half-life in the body, depending on the desired outcomes.

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A fluorescent probe for butyrylcholinesterase activity in human serum based on a fluorophore with specific binding affinity for human serum albumin

Chemical Communications ◽

10.1039/c9cc07737e ◽

2019 ◽

Vol 55 (97) ◽

pp. 14574-14577 ◽

Cited By ~ 8

Author(s):

Soyeon Yoo ◽

Min Su Han

Keyword(s):

Human Serum Albumin ◽

Serum Albumin ◽

Human Serum ◽

Fluorescent Probe ◽

Binding Affinity ◽

Specific Binding ◽

Turn On ◽

High Binding ◽

Butyrylcholinesterase Activity ◽

High Binding Affinity

We report a novel turn-on sensing probe for the detection of butyrylcholinesterase activity in human serum using a fluorophore with high binding affinity for HSA.

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