Characterization of a common intermediate of pea lectin in the folding pathway induced by TFE and HFIP

How methyl cyanide induces aggregation in all-alpha proteins: A case study in four albumins

“…Mean Residual Ellipticity (MRE) at 222 nm is used as a function for percentage of ␣ helicity of a protein [25,26]. The changes in MRE at 222 nm with the increasing concentration of MeCN was monitored in the range of 0-40% (v/v) MeCN (pre-aggregation zone), for all the four albumins and the results have plotted, in Fig.…”

“…A lot of work has been done to understand the effect of alcohols on various proteins and the degree of formation of alpha helix in them [25,26]. However, relatively much less work has been done to understand the effect of MeCN on a predominantly alpha helical model protein, like albumin.…”

Effect of polyamines on the structure, thermal stability and 2,2,2-trifluoroethanol-induced aggregation of α-chymotrypsin

“…It is well known that various alcohols, especially those substituted with fluorine such as TFE, can stabilize and induce ␣-helical structures in peptides and proteins [19][20][21][22][23][24][25][26]29]. To monitor the TFE-induced changes in ␣-chymotrypsin secondary structure, the mean-residue ellipticity of the protein at 208 and 217 nm, which are normally regarded as indicators of ␣-helix and ␤-strand abundance, was measured at various TFE concentrations.…”

“…Various alcohols, especially those substituted with fluorine such as 2,2,2-trifluoroethanol (TFE) and 3,3,3,3 ,3 ,3 -hexafluoro-2-propanol (HFIP) have been found very effective in causing protein denaturation and inducing ␣-helical structure in peptides [20][21][22][23]. This effect can presumably be attributed to low dielectric constants of alcohols [24,25].…”

“…Alcohol-induced conformational transitions of proteins have been found to be similar to those induced by the lipid environment of biological membranes [28], making such studies useful regarding protein conformation in membranes. Furthermore, characterizing the alcohol-induced intermediate states of the proteins may shed light on the mechanism of their folding [22,23,29].…”