In Vitro Elucidation of the Folding Intermediates and Aggregate Formation of Hemoglobin Induced by Acetonitrile: A Multispectroscopic Approach

Abstract

Acetonitrile is a mild solvent, which induces β-sheet conformation in proteins. The global conformational changes in Hb in the presence of ACN were studied using intrinsic fluorescence experiments, acrylamide quenching, ANS fluorescence measurements, soret absorbance spectroscopy, fourier transform infrared spectroscopy, circular dichroism, thioflavin T and congo red assay. Molecular docking showed the binding of hydrophobic residues of Hb to ACN. Hb exists as a partially unfolded intermediate state at 30% v/v ACN. Hb aggregates were obtained at 60% v/v ACN concentration, which were further confirmed by transmission electron microscopy.

Peppermint extract inhibits protein aggregation

“…The presence of a mild solvent causes an increase in the β-sheet conformation in proteins (Furkan et al 2016;Simon et al 2012), thus the organic solvents can be used to prepare amyloid fibrils (Nematilay et al 2014;Kotormán et al 2015). Amyloid growth detection is generally performed by measuring the turbidity of the solution (Zhao et al 2016;Kasi and Kotormán 2019b).…”

The Anti-amyloidogenic effect of natural product extracts on amyloid-like fibril formation of trypsin in aqueous organic solvents

“…In order to demonstrate the inhibitory effect of chili extract on PMS-trypsin fibrillation by structural change, we analysed the FTIR spectrum of protein in 10 mM phosphate-buffered Electronic circular dichroism analysis in the far UV wavelength range (185-260 nm) was conducted to determine the changes in the secondary structure of PMS-trypsin in aqueous ethanol at pH 7.0. The presence of a mild solvent causes an increase in the β-sheet conformation in proteins (Furkan et al, 2016). Conversion of the secondary structure of PMS-trypsin in the presence of 60% ethanol takes place immediately.…”