Interaction of Bovine (BSA), Rabbit (RSA), and Porcine (PSA) Serum Albumins with Cationic Single-Chain/Gemini Surfactants: A Comparative Study

Abstract

The interactions among bovine, rabbit, and porcine serum albumins and single-chain cationic surfactant cetyltrimethylammonium bromide (CTAB) versus its gemini counterpart (designated as G4) have been studied. The studies were carried out in an aqueous medium at pH 7.0 using UV, intrinsic and extrinsic fluorescence spectroscopy, and far-UV circular dichroism techniques. The results indicate that compared to CTAB, G4 interacts strongly with the serum albumins, resulting in a significantly larger unfolding or decrease in alpha-helical content as reflected by the significantly larger decrease in ellipticity in the far-UV range. Unlike CTAB, a remarkable increase in the alpha-helical content of BSA at 625 microM G4 and at 250 microM G4 for RSA and PSA is observed. The appearance of conformational changes and saturation points in the proteins occurs at considerably lower [G4] compared to [CTAB]. The results obtained from the multi-technique approach are ascribed to the stronger forces in G4 owing to the presence of two charged headgroups and two hydrocarbon tails. Keeping the results in view, it is suggested that the gemini surfactants may be effectively used in the renaturation of proteins produced in genetically engineered cells via the artificial chaperone protocol and may also prove useful in drug delivery as solubilizing agents to recover proteins from insoluble inclusion bodies.

Interactions of bovine serum albumin with cationic imidazolium and quaternary ammonium gemini surfactants: Effects of surfactant architecture

“…This confirms the conclusion that imidazolium surfactants interact with BSA more strongly than quaternary ammonium surfactants with the same hydrophobic chain. The explanations may be that imidazolium surfactants display the strong p-p interaction, namely, the aromatic ring stacking between the imidazolium rings and the residues (such as Trp, Tyr, and Phe) in BSA, besides electrostatic and hydrophobic interactions [39,40,47], attributing to the existence of aromatic functional groups imidazolium ions for [C n -4-C n im]Br 2 or [C 12 mim]Br. This aromatic ring stacking leads to the more expanding of polypeptide and the larger unfolding of BSA.…”

“…As seen in Fig. 6, the CD spectra of BSA exhibit two negative bands in the UV region at 208 and 222 nm, which is the characteristic of the a-helical structure of protein [22,40,48]. At low [C 12 -4-C 12 im]Br 2 concentrations (60.002 mmol L À1 ), there is little change in the negative ellipticity at 208 and 222 nm, but at high concentrations (>0.01 mmol L À1 ), the negative ellipticity decreases.…”

“…Recent investigations on the interaction of BSA/gemini surfactant [39][40][41][42][43] have revealed that such surfactants interact more efficiently with proteins as compared with conventional single chain surfactants. As a new generation of amphiphilic molecule [39][40][41][42][43][44][45][46], gemini surfactants are characterized by two hydrophobic chains and two polar headgroups covalently linked through a spacer group. Compared with conventional surfactants, they have a number of unique properties [45], such as lower critical micelle concentration (cmc), higher adsorption efficiency, and better wetting property.…”

Fluorescence Spectroscopy Study on the Interaction of Acetal Cleavable Anionic Surfactants and Bovine Serum Albumin

“…This also encourages the interest in researching the synthesis of simple and practical surfactants and developing desirable methods in proteomic research. Recently, protein-gemini surfactants interactions have been developed because these surfactants have a low critical micelle concentration (CMC), a low Krafft temperature, a strong hydrophobic microdomain, and a superior viscous behavior in comparison to the conventional single-chain surfactants [15][16][17][18]. However, the complex synthesis and purification procedures associated with these surfactants often lead to expensive consumption which limits the application of gemini surfactants in proteomic research.…”

Structural Stability as a Probe for Molecular Evolution of Homologous Albumins Studied by Spectroscopy and Bioinformatics

“…Within mammalian systems, albumins show high sequence similarity of gene sequence, hence structure and function [1]. But very few works have been done to understand variations in physical properties of mammalian albumins [6][7][8]. In previous communication, we have found that the four serum albumins from human, rabbit, porcine and bovine; i.e., HSA, RSA, PSA and BSA show similar aggregation patterns in the presence of methyl cyanide, with some clear indications of species-dependent variations [7].…”