Elucidating the interaction of clofazimine with bovine liver catalase; a comprehensive spectroscopic and molecular docking approach

Abstract

Nowadays, understanding of interface between protein and drugs has become an active research area of interest. These types of interactions provide structural guidelines in drug design with greater clinical efficacy. Thus, structural changes in catalase induced by clofazimine were monitored by various biophysical techniques including UV-visible spectrometer, fluorescence spectroscopy, circular dichroism, and dynamic light scattering techniques. Increase in absorption spectra (UV-visible spectrum) confers the complex formation between drug and protein. Fluorescence quenching with a binding constants of 2.47 × 10 M revealed that clofazimine binds with protein. Using fluorescence resonance energy transfer, the distance (r) between the protein (donor) and drug (acceptor) was found to be 2.89 nm. Negative Gibbs free energy change (ΔG°) revealed that binding process is spontaneous. In addition, an increase in α-helicity was observed by far-UV circular dichroism spectra by adding clofazimine to protein. Dynamic light scattering results indicate that topology of bovine liver catalase was slightly altered in the presence of clofazimine. Hydrophobic interactions are the main forces between clofazimine and catalase interaction as depicted by molecular docking studies. Apart from hydrophobic interactions, some hydrogen bonding was also observed during docking method. The results obtained from the present study may establish abundant in optimizing the properties of ligand-protein mixtures relevant for numerous formulations.

A study on the interaction between cadmium and α‐chymotrypsin and the underlying mechanisms

“…The absorbance of the backbone peak decreased with the addition of CdCl 2 , suggesting that the interaction of CdCl 2 with α‐ChT led to the loosening of the protein skeleton . The weak one around 280 nm is associated with the microenvironmental changes in aromatic amino acid (Trp and Tyr) residues . The inset in Figure shows that the absorbance of the peak around 280 nm increased with the addition of CdCl 2 , implying that the aromatic acid residues of α‐ChT were exposed to a more hydrophilic environment.…”

Isolation and identification of dipeptidyl peptidase‐IV inhibitory peptides from Sacha inchi meal

“…UV spectroscopy can be used to determine whether the electronic activity range of DPP‐IV has changed under the action of synthetic peptides. Generally, the absorption band between 200 and 220 nm is mainly provided by carbon–oxygen double bonds and aromatic hydrocarbons 17 . Fig.…”

Exploring the interactions of a Tb(III)–quercetin complex with serum albumins (HSA and BSA): spectroscopic and molecular docking studies

“…fluorescence resonance energy transfer (FRET) measurements were carried out at 298 K (eqn ): where E , F and F 0 represent the efficiency of energy transfer and the fluorescence intensities of HSA/BSA in the presence or absence of Tb–QUE complex, respectively, ‘ r ’ denotes the distance between HSA/BSA (donor) and the Tb–QUE complex (acceptor), and R 0 represents the critical distance when the transfer efficiency is 50% (eqn ): where K 2 denotes the spatial orientation factor between the donor emission and the acceptor absorption, n is the refractive index of the medium, Φ corresponds to the fluorescence quantum yield of the HSA/BSA and J is the spectral overlap integral between HSA/BSA and Tb–QUE complex. In this study, K 2 = 2/3, n = 1.336 and Φ = 0.15 (eqn ): where F(λ) and ε(λ) are the fluorescence intensity of the HSA/BSA and the molar absorption coefficient of the Tb–QUE complex …”