Simplified Synthesis and Stability Assessment of Aflatoxin B1-Lysine and Aflatoxin G1-Lysine

Aflatoxins B1 (AFB1) and G1 (AFG1) are carcinogenic mycotoxins that contaminate crops such as maize and groundnuts worldwide. The broadly accepted method to assess chronic human aflatoxin exposure is by quantifying the amount of aflatoxin adducted to human serum albumin. This has been reported using ELISA, HPLC, or LC-MS/MS to measure the amount of AFB1-lysine released after proteolysis of serum albumin. LC-MS/MS is the most accurate method but requires both isotopically labelled and unlabelled AFB1-lysine standards, which are not commercially available. In this work, we report a simplified synthetic route to produce unlabelled, deuterated and 13C6 15N2 labelled aflatoxin B1-lysine and for the first-time aflatoxin G1-lysine. Additionally, we report on the stability of these compounds during storage. This simplified synthetic approach will make the production of these important standards more feasible for laboratories performing aflatoxin exposure studies.

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The Influence of Oxidative Stress on Serum Albumin Structure as a Carrier of Selected Diazaphenothiazine with Potential Anticancer Activity

Pharmaceuticals ◽

10.3390/ph14030285 ◽

2021 ◽

Vol 14 (3) ◽

pp. 285

Author(s):

Małgorzata Maciążek-Jurczyk ◽

Beata Morak-Młodawska ◽

Małgorzata Jeleń ◽

Wiktoria Kopeć ◽

Agnieszka Szkudlarek ◽

...

Keyword(s):

Human Serum Albumin ◽

Serum Albumin ◽

Human Serum ◽

Anticancer Activity ◽

Drug Distribution ◽

Cd Spectroscopy ◽

Drug Binding ◽

Protein Activity ◽

Chloramine T ◽

The Stability

Albumin is one of the most important proteins in human blood. Among its multiple functions, drug binding is crucial in terms of drug distribution in human body. This protein undergoes many modifications that are certain to influence protein activity and affect its structure. One such reaction is albumin oxidation. Chloramine T is a strong oxidant. Solutions of human serum albumin, both non-modified and modified by chloramine T, were examined with the use of fluorescence, absorption and circular dichroism (CD) spectroscopy. 10H-3,6-diazaphenothiazine (DAPT) has anticancer activity and it has been studied for the first time in terms of binding with human serum albumin—its potential as a transporting protein. Using fluorescence spectroscopy, in the presence of dansylated amino acids, dansyl-l-glutamine (dGlu), dansyl-l-proline (dPro), DAPT binding with two main albumin sites—in subdomain IIA and IIIA—has been evaluated. Based on the conducted data, in order to measure the stability of DAPT complexes with human (HSA) and oxidized (oHSA) serum albumin, association constant (Ka) for ligand-HSA and ligand-oHSA complexes were calculated. It has been presumed that oxidation is not an important issue in terms of 10H-3,6-diazaphenothiazine binding to albumin. It means that the distribution of this substance is similar regardless of changes in albumin structure caused by oxidation, natural occurring in the organism.

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Comparison of the stability of Y-90-, Lu-177- and Ga-68- labeled human serum albumin microspheres (DOTA-HSAM)

Nuclear Medicine and Biology ◽

10.1016/j.nucmedbio.2010.05.004 ◽

2010 ◽

Vol 37 (8) ◽

pp. 861-867 ◽

Cited By ~ 20

Author(s):

Gerd Wunderlich ◽

Eik Schiller ◽

Ralf Bergmann ◽

Hans-Jürgen Pietzsch

Keyword(s):

Human Serum Albumin ◽

Serum Albumin ◽

Human Serum ◽

Albumin Microspheres ◽

The Stability

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Spectroscopic and molecular modeling studies of human serum albumin interaction with propyl gallate

RSC Advances ◽

10.1039/c4ra11103f ◽

2014 ◽

Vol 4 (110) ◽

pp. 64559-64564 ◽

Cited By ~ 36

Author(s):

Jafar Ezzati Nazhad Dolatabadi ◽

Vahid Panahi-Azar ◽

Abolfazl Barzegar ◽

Ali Akbar Jamali ◽

Fahimeh Kheirdoosh ◽

...

Keyword(s):

Molecular Modeling ◽

Human Serum Albumin ◽

Fluorescence Quenching ◽

Serum Albumin ◽

Human Serum ◽

Propyl Gallate ◽

Fluorescence Quenching Method ◽

Molecular Modeling Studies ◽

Quenching Method ◽

First Time

For the first time, PG interaction with HSA using fluorescence quenching method, circular dichroism spectroscopy and molecular modeling was investigated.

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Analysis of Binding Interactions of Ramipril and Quercetin on Human Serum Albumin: A Novel Method in Affinity Evaluation

Molecules ◽

10.3390/molecules25030547 ◽

2020 ◽

Vol 25 (3) ◽

pp. 547

Author(s):

Zuzana Vaneková ◽

Lukáš Hubčík ◽

José Luis Toca-Herrera ◽

Paul Georg Furtműller ◽

Pavel Mučaji ◽

...

Keyword(s):

Human Serum Albumin ◽

Serum Albumin ◽

Human Serum ◽

Accurate Method ◽

Cd Spectroscopy ◽

Future Research ◽

Binding Interactions ◽

Allosteric Interactions ◽

Flavonoid Quercetin ◽

High Concentrations

The aim of this study was to analyze the binding interactions between a common antihypertensive drug (ramipril, R) and the widely distributed plant flavonoid quercetin (Q), in the presence of human serum albumin (HSA). From the observed fluorescence spectra of the (HSA + R) system we can assume that ramipril is also one of the Site 3 ligands—similar to fusidic acid—the binding of which has been proven by RTG crystallography. Our claim is supported by near-UV CD spectroscopy, microscale themophoresis and molecular modeling. The presence of R slightly inhibited the subsequent binding of Q to HSA and, on the contrary, the pre-incubation of HSA with Q caused a stronger binding of R, most likely due to allosteric interactions. At high concentrations, R is also able to displace Q from its binding site. The dissociation constant KD for the binding of R is more than hundredfold larger than for Q, which means that R is a very weak binder to HSA. The knowledge of qualitative and quantitative parameters of R, as well as the methods used in this study, are important for future research into HSA binding. This study shows the importance of implementing other methods for KD determination. Microscale thermophoresis has proved to be a novel, practical and accurate method for KD determination on HSA, especially in cases when fluorescence spectroscopy is unable to produce usable results.

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Analysis of aflatoxin B1-human serum albumin adducts by a sandwich enzyme-linked immunosorbent assay

JSM Mycotoxins ◽

10.2520/myco1975.1996.43_43 ◽

1996 ◽

Vol 1996 (43) ◽

pp. 43-46 ◽

Cited By ~ 3

Author(s):

Osamu KAWAMURA ◽

J.-M. LIM ◽

Hiroki OKUMURA ◽

Sigefumi KISHIMOTO ◽

G. CHEN ◽

...

Keyword(s):

Human Serum Albumin ◽

Serum Albumin ◽

Human Serum ◽

Immunosorbent Assay ◽

Aflatoxin B1 ◽

Enzyme Linked Immunosorbent Assay

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Human Serum Albumin Cys34Oxidative Modifications following Infiltration in the Carotid Atherosclerotic Plaque

Oxidative Medicine and Cellular Longevity ◽

10.1155/2014/690953 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 7

Author(s):

Antonio Junior Lepedda ◽

Angelo Zinellu ◽

Gabriele Nieddu ◽

Pierina De Muro ◽

Ciriaco Carru ◽

...

Keyword(s):

Human Serum Albumin ◽

Serum Albumin ◽

Human Serum ◽

Carotid Endarterectomy ◽

Atherosclerotic Plaque ◽

Plasma Samples ◽

Carotid Atherosclerotic Plaque ◽

Sds Page ◽

Oxidative Modifications ◽

First Time

Objectives.To evaluate if the prooxidant environment present in atherosclerotic plaque may oxidatively modify filtered albumin.Methods.Fluorescein-5-maleimide labelled plasma samples and plaque extracts from 27 patients who had undergone carotid endarterectomy were analysed through nonreducing SDS-PAGE for albumin-Cys34oxidation. Furthermore, degree and pattern of S-thiolation in both circulating and plaque-filtered albumin were assayed.Results.Albumin filtered in the atherosclerotic plaque showed higher levels of Cys34oxidative modifications than the corresponding circulating form as well as different patterns of S-thiolation.Conclusions.Data indicate that the circulating albumin, once filtered in plaque, undergoes Cys34oxidative modifications and demonstrate for the first time that albumin is a homocysteine and cysteinylglycine vehicle inside the plaque environment.

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The Effects of Drug Complexation on the Stability and Conformation of Human Serum Albumin: Protein Unfolding

Cell Biochemistry and Biophysics ◽

10.1385/cbb:45:2:203 ◽

2006 ◽

Vol 45 (2) ◽

pp. 203-214 ◽

Cited By ~ 85

Author(s):

A. Ahmed-Ouameur ◽

S. Diamantoglou ◽

M. R. Sedaghat-Herati ◽

Sh. Nafisi ◽

R. Carpentier ◽

...

Keyword(s):

Human Serum Albumin ◽

Serum Albumin ◽

Human Serum ◽

Protein Unfolding ◽

The Stability

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Cisplatin binding to human serum albumin: a structural study

Chemical Communications ◽

10.1039/c5cc01751c ◽

2015 ◽

Vol 51 (46) ◽

pp. 9436-9439 ◽

Cited By ~ 73

Author(s):

Giarita Ferraro ◽

Lara Massai ◽

Luigi Messori ◽

Antonello Merlino

Keyword(s):

Human Serum Albumin ◽

Serum Albumin ◽

Human Serum ◽

Crystal Structures ◽

Structural Study ◽

X Ray ◽

X Ray Crystallography ◽

First Time

The reaction between cisplatin and human serum albumin (HSA) was investigated by X-ray crystallography and crystal structures of the cisplatin/HSA adduct were eventually solved for the first time.

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