Insights into the binding of 2-aminobenzothiazole with human serum albumin (HSA): spectroscopic investigation and molecular modeling studies.
As one of the important thiazole derivatives, 2-aminobenzothiazole (2-ABT) has been widely used as a structural unit in the synthesis of anti-oxidants, anti-inflammatories, herbicides, antibiotics, and thermoplastic polymers. In this study, the interaction of 2-ABT with human serum albumin (HSA) was investigated in vitro under simulated physiological conditions, using multi-spectroscopic techniques and a molecular modeling study. The binding constant and binding sites were determined through fluorescence quenching spectra. The site-competitive replacement experiments revealed that the precise binding site of 2-ABT on HSA was site II (subdomain IIIA). Moreover, molecular docking results illustrated the electrostatic interaction between Glu 450 and 2-ABT, in accordance with the conclusions from the calculated thermodynamic parameters and the effect of ionic strength. The effect of 2-ABT on the conformational changes of HSA were evaluated by ultraviolet-visible (UV-Vis) absorption, three-dimensional (3D) fluorescence, synchronous fluorescence, and circular dichroism (CD) spectroscopy. This work facilitates comprehensive understanding of the binding of 2-ABT with HSA, contributing to evaluate the molecular transportation mechanism and biotoxicity of 2-aminobenzothiazole derivatives in vivo.
Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment and Health, Jinan, PR China.
Yajing
Y
Sun
Baoling
B
Su
Qifei
Q
Xu
Rutao
R
Liu
D052160:Benzothiazoles / Q000737:chemistry* / Q000378:metabolism*; D002942:Circular Dichroism; D006801:Humans; D008958:Models, Molecular; D009994:Osmolar Concentration; D011485:Protein Binding; D012709:Serum Albumin / Q000737:chemistry* / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D013816:Thermodynamics
D052160:Benzothiazoles; D012709:Serum Albumin; C523775:aminobenzothiazole compound