Investigating the Interaction of Fe Nanoparticles with Lysozyme by Biophysical and Molecular Docking Studies

Abstract

Herein, the interaction of hen egg white lysozyme (HEWL) with iron nanoparticle (Fe NP) was investigated by spectroscopic and docking studies. The zeta potential analysis revealed that addition of Fe NP (6.45±1.03 mV) to HEWL (8.57±0.54 mV) can cause to greater charge distribution of nanoparticle-protein system (17.33±1.84 mV). In addition, dynamic light scattering (DLS) study revealed that addition of Fe NP (92.95±6.11 nm) to HEWL (2.68±0.37 nm) increases suspension potential of protein/nanoparticle system (51.17±3.19 nm). Fluorescence quenching studies reveled that both static and dynamic quenching mechanism occur and hydrogen bond and van der Waals interaction give rise to protein-NP system. Synchronous fluorescence spectroscopy of HEWL in the presence of Fe NP showed that the emission maximum wavelength of tryptophan (Trp) residues undergoes a red-shift. ANS fluorescence data indicated a dramatic exposure of hydrophobic residues to the solvent. The considerable reduction in melting temperature (T(m)) of HEWL after addition of Fe NP determines an unfavorable interaction system. Furthermore circular dichoroism (CD) experiments demonstrated that, the secondary structure of HEWL has not changed with increasing Fe NP concentrations; however, some conformational changes occur in tertiary structure of HEWL. Moreover, protein–ligand docking study confirmed that the Fe NP forms hydrogen bond contacts with HEWL.

Physicochemical Study of the Interaction between Gold Nanoparticles and Lipase from Candida sp. (CALB): Insights into the Nano-Bio Interface

“…48,52,75,82,83 Besides, the more negative zeta potential value for AuNPs@CALB suggests superior stability in relation to SA CALB/AuNPs, since the increase of repulsive forces reduces the tendency of colloidal aggregation. 77 The zeta potential experiments confirmed that CALB adsorption took place on AuNPs surfaces for both AuNPs@CALB and SA CALB/AuNPs. 84 The adsorption was also confirmed by SDS page (Figure S2, SI section).…”

“…76 The zeta potential (ζ) determination is a suitable technique for the assessment of the colloidal stability which plays a central role in the in vivo application of this system. 77 The ζ of citrate-stabilized AuNPs was −48.4 ± 2.6 mV. This value is indicative of the high stability of the particles.…”

A health concern regarding the protein corona, aggregation and disaggregation

“…Therefore, it is important to determine the relationship between chemical functionalities of NPs and their biological activities, for example, in NP-induced targeted drug delivery systems and medicinal applications [187]. Additionally, NPs can destabilize the structure of adsorbed proteins and vice versa, and subsequently change the function of proteins and colloidal stability of NPs [188].…”

Engineering Proteins at Interfaces: From Complementary Characterization to Material Surfaces with Designed Functions

“…Thec ontrolled adsorption of specific proteins from biological media is still in its infancy,a nd the findings discussed above clearly indicate the importance of proteins at interfaces and their crucial roles in dictating cellular uptake.I no rder to exert greater control over the interfaces and subsequent nanocarrier properties,t he interaction between proteins and nanoparticle surfaces can be predefined by design through controlled protein adsorption. Va rious nanoparticles such as metals, [151] semiconductors, [152] or nanodiamonds [153] have been stabilized by this emerging and versatile protein passivation strategy to enable in vitro and in vivo bioapplications.T here are different ways to add the desired proteins as stable bioadhesives to the nanoparticles, for example,t hrough electrostatic interactions, [154] non-covalent interactions, [155] or ligand-metal interactions. [152] As proteins offer multiple carboxylic acid, amino,a nd thiol/ disulfide groups,l igand exchange of weakly bound nanoparticle surface groups by the desired protein represents am ethod of choice to passivate,f or example,q uantum dots.…”