Novel binding studies of human serum albumin with trans-feruloyl maslinic acid

Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India.
Journal of photochemistry and photobiology. B, Biology (Impact Factor: 2.96). 02/2009; 95(2):81-8. DOI: 10.1016/j.jphotobiol.2009.01.002
Source: PubMed

ABSTRACT Human serum albumin (HSA) is a predominant protein in the blood. Most drugs can bind to HSA and be transported to target locations of the body. For this study, we have extracted 3-trans-feruloyl maslinic acid (FMA) from the medicinal plant Tetracera asiatica, its a non-fluorescent derivative have potent anti-cancer, anti-HIV, anti-diabetic, and anti-inflammatory activities. The binding constant of the compound with HSA, calculated from fluorescence data, was found as K(FMA)=1.42+/-0.01 x 10(8) M(-1), which corresponds to 10.9 kcal M(-1) of free energy. Furthermore, microTOF-Q mass spectrometry data showed binding of FMA at nanomolar concentrations of FMA to free HSA. The study detected a mass increase from 66,560 Da (free HSA) to 67,919 Da (HSA+drug). This indicated a strong binding of FMA to HSA, resulting in an increase of the protein's absorbance and fluorescence. The secondary structure of HSA+FMA (0.1 mM) complexes showed the protein secondary structure became partially unfolded upon interaction of FMA with HSA, as well as indicating that HSA-FMA complexes were formed. Docking experiments uncovered the binding mode of FMA in HSA molecule. It was found that FMA binds strongly in different places with hydrogen bonding at IB domain of Arg 114, Leu 115 and Asp 173.

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Available from: Babu Sudhamalla, Sep 28, 2015
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    • "Among serum albumins, bovine serum albumin (BSA) has the advantages of low cost, stability, ready availability, and unusual ligand-binding properties. Despite the ample literature, however, little firm knowledge is available on the binding between albumin and triterpenoids [14] [15] [16] [17], especially on structure-affinity relationship of these compounds with albumin. Clearly, an understanding of the interaction of these pharmaceuticals with albumin is needed to gain insight into their therapeutic effectiveness. "
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    Journal of Molecular Liquids 04/2015; 208. DOI:10.1016/j.molliq.2015.04.050 · 2.52 Impact Factor
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    • "Tajmir - Riahi , 2009 ; Pu , Jiang , & Chen , 2013 ; Sułkow - ska , 2002 ) . Recently , we have reported quenching of HSA fluorescence with biologically significant drug candidates ( Garg et al . , 2013 ; Gokara et al . , 2010 ; Gokara et al . , 2013 ; Subramanyam et al . , 2009b ; Sudhamalla et al . , 2010 ) . With an increasing concentration of chitooligomers with HSA and AGP , the absorption at excitation ( 285 nm ) and emission ( 360 nm ) wavelength introduces inner filter effect that may decrease the fluorescence intensity and results in a nonlinear relationship between the observed fluorescence intensity a"
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    ABSTRACT: Chitosan is a naturally occurring deacetylated derivative of chitin with versatile biological activities. Here, we studied the interaction of chitosan oligomers with low degree of polymerization such as chitosan monomer (CM), chitosan dimer (CD), and chitosan trimer (CT) with human serum albumin (HSA) a major blood carrier protein and α-1-glycoprotein (AGP). Since, HSA and AGP are the two important plasma proteins that determine the drug disposition and affect the fate of distribution of drugs. Fluorescence emission spectra indicated that CM, CD, and CT had binding constants of KCM = 6.2 ± .01 × 10(5) M(-1), KCD = 5.0 ± .01 × 10(4) M(-1), and KCT = 1.6 ± .01 × 10(6) M(-1), respectively, suggesting strong binding with HSA. However, binding of chitooligomers with AGP was insignificant. Thermodynamic and molecular docking analysis indicated that hydrogen bonds and also hydrophobic interaction played an important role in stabilizing the HSA-chitooligomer complexes with free energies of -7.87, -6.35, and -8.4 Kcal/mol for CM, CD, and CT, respectively. Further, circular dichroism studies indicated a minor unfolding of HSA secondary structure, upon interaction with chitooligomers, which are supported with fluctuations of root mean square deviation (RMSD) and radius of gyration (Rg) of HSA. Docking analysis revealed that all three chitooligomers were bound to HSA within subdomain IIA (Site I). In addition, RMSD and Rg analysis depicted that HSA-chitooligomer complexes stabilized at around 4.5 ns. These results suggest that HSA might serve as a carrier in delivering chitooligomers to target tissues than AGP which has pharmacological importance.
    Journal of biomolecular Structure & Dynamics 12/2013; 33(1). DOI:10.1080/07391102.2013.868321 · 2.92 Impact Factor
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    • "Fluorescence quenching of the protein upon drug binding was used to find the drug-protein interactions and measure the binding affinity of the drug to HSA [53]. Figure 2 depicts the room temperature fluorescence emission spectra of HSA obtained fluorescence maximum at 362 nm, which is in agreement with our previous reports [30], [31]. In the presence of different concentrations of coumarin derivatives (0.001 to 0.01 mM) with the physiological phosphate buffer pH 7.2, our results showed that, with the increasing concentrations of coumarin derivatives and a fixed concentration of HSA (0.001 mM), the maximum fluorescence (362 nm) of HSA was quenched upon binding of coumarin derivatives (Figure 2). "
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    PLoS ONE 05/2013; 8(5):e63805. DOI:10.1371/journal.pone.0063805 · 3.23 Impact Factor
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