Interaction of cyclodextrins with human and bovine serum albumins: a combined spectroscopic and computational investigation

Interaction of cyclodextrins (CDs) with the two most abundant proteins, namely human serum albumin (HSA) and bovine serum albumin (BSA), has been investigated using steady-state and time-resolved fluorometric techniques, circular dichroism measurements and molecular docking simulation. The study reveals that the three CDs interact differently on the fluorescence and fluorescence lifetimes of the serum albumins. However, fluorescence anisotropy and circular dichroism are not affected. Depending on their size, different CDs bind to the serum albumins in different positions, resulting in changes in the spectral behaviour of the proteins. Docking study suggests the probable binding sites of the three CDs with the proteins. Combined experimental and computational studies imply that sufficiently high concentration of CDs causes loosening of the rigid structures of these transport proteins, although their secondary structures remain intact. Thus, CDs are found to be safe for the serum proteins from the structural point of view

Sequestration of Drugs from Biomolecular and Biomimicking Environments: Spectroscopic and Calorimetric Studies

The binding of drugs to nucleic acids, proteins, lipids, amino acids, and other biological receptors is necessary for the transportation of drugs. However, various side effects may also originate if the bound drug molecules are not dissociated from the carrier, especially with the aid of non-toxic agents. The sequestration of small drug molecules bound to biomolecules is thus central to counter issues related to drug overdose and drug detoxification. In this article, we aim to present several methods used for the dissociation of small drug molecules bound to different biological and biomimicking assemblies under in vitro experimental conditions. To this effect, the application of various molecular assemblies, like micelles, mixed micelles, molecular containers, like β-cyclodextrin, cucurbit[7]uril hydrate, etc., has been discussed. Herein, we also try to shed light on the driving forces underlying such sequestration processes through spectroscopic and calorimetric techniques

On Jordan left-I-centralizers of prime and semiprime gamma rings with involution

Let M be a 2-torsion free Γ-ring with involution I satisfying the condition xαyβz=xβyαz for all x,y,z∈M and α,β∈Γ. The object of our paper is to show that every Jordan left-I-centralizer on a semiprime Γ-ring with involution I, is a reverse left-I-centralizer. We solve some functional equations in prime and semiprime Γ-rings with involution I by means of the above results. Moreover, we discuss some more related results

A digital scrambling method based on balancing numbers

In this article, a new approach to the study of image scrambling based on balancing numbers, balancing transformation is presented. The properties of the proposed transformation and its periodicity are studied in details. In order to reduce the periods of the balancing transformation, we separate the consecutive pixels as far as possible from each other in that domain of the digital images.Publisher's Versio

Binding of an anionic fluorescent probe with calf thymus DNA and effect of salt on the probe–DNA binding: a spectroscopic and molecular docking investigation

Binding interaction of a biologically relevant anionic probe molecule, 8-anilino-1-naphthalene sulfonate (ANS) with calf-thymus deoxyribonucleic acid (ctDNA) has been investigated exploiting vivid spectroscopic techniques together with molecular docking study. Significant modifications in the absorption and emission profiles, the determined binding constant, micropolarity analysis, circular dichroism (CD) spectral study, comparative binding study with ethidium bromide (EtBr)—an intercalative binder, thermometric experiment relating to the helix melting of ctDNA and blind molecular docking simulation confirm the groove binding of ANS with ctDNA. Furthermore, a remarkable enhancement is observed in the fluorescence intensity as well as in the fluorescence lifetime of the DNA-bound probe with the addition of salts. Reduction in the electrostatic repulsion between the ANS and DNA at high salt concentration has been assigned responsible for this observation. Besides providing an insight into the probe–DNA interaction, the work implies that the binding interaction of a negatively charged probe with DNA can be enhanced considerably by the addition of salts