Solvent Perturbation of Protein Structures - A Review Study with Lectins

Abstract

Use of organic molecules as co-solvent with water, the ubiquitous biological solvent, to perturb the structure of proteins is popular in the research area of protein structure and folding. These organic co-solvents are believed to somehow mimic the environment near the cell membrane. Apart from that they induce non-native states which can be present in the protein folding pathway or those states also may be representative of the off pathway structures leading to amyloid formation, responsible for various fatal diseases. In this review, we shall focus on organic co-solvent induced structure perturbation of various members of lectin family. Lectins are excellent model systems for protein folding study because of its wide occurrence, diverse structure and versatile biological functions. Lectins were mainly perturbed by two fluoroalcohols – 2,2,2- trifluoroethanol and 1,1,1,3,3,3-hexafluoroisopropanol whereas glycerol, ethylene glycol and polyethylene glycols were used in some cases. Overall, all native lectins were denatured by alcohols and most of the denatured lectins have predominant helical secondary structure. But characterization of the helical states and the transition pathway for various lectins revealed diverse result.

Hexafluoroisopropanol: the magical solvent for Pd-catalyzed C–H activation

“…Additionally, hexafluoroisopropanol indirectly influences the structural modification of protein and lipid layers of different biological membranes ( Scheme 1C ). 15 Apart from peptide chemistry, HFIP is potential enough to produce lipid bilayer leakage and alter the biochemical properties of the lipid phase. 16 …”

Direct Identification of Amyloid Peptide Fragments in Human α-Synuclein Based on Consecutive Hydrophobic Amino Acids

“…Because hydrophobic interaction was supposed to be a crucial driving force for the peptides’ amyloid aggregation, we further tested their aggregation potency in the mixture of PBS and tetrahydrofuran (THF). Compared with water, THF is a more hydrophobic solvent, so that it may bind with hydrophobic face of proteins or peptides, which might inhibit their aggregation by disturbing the intermolecular hydrophobic interaction directly or by perturbing the structure of protein or peptide monomers. , As shown in Figure C, aggregation ability of all amyloid peptides was significantly inhibited by THF in a concentration-dependent manner, suggesting the importance of hydrophobic interaction in the aggregation process. Furthermore, we also tested the effect of THF on preformed aggregates of full-length HS.…”

The Chemical and Cytotoxic Properties of Sambucus nigra Extracts—A Natural Food Colorant

“…Lectins are also listed as active substances in elderberry extracts [51]. The extract B2 should not contain lectins in their native form since proteins, including lectins, are denatured with high concentrations of alcohols [52]. In the case of the B2 extract, high-percentage ethyl alcohol was used for the elution.…”