Mapping the amide-I vibrations of model dipeptides with secondary structure sensitivity and amino acid residue specificity, and its application to amyloid β-peptide in aqueous solution

Add time:07/27/2019    Source:sciencedirect.com

Vibrational spectroscopy has been known as particularly well-suited for deciphering the polypeptide's structure. To decode structural information encoded in IR spectra, we developed amide-I frequency maps on the basis of model dipeptides to correlate the amide-I frequency of interest to the combination of the calculated secondary structure dependent amide-I frequency by using DFT method and the electrostatic potentials that projected onto the amide unit from the micro-environment within molecular mechanics force field. The constructed maps were applied to model dipeptides and amyloid β-peptide fragment (Aβ25–35). The dipeptide specified map (DS map) and the hybrid map (HYB map) predicted amide-I bands of Aβ25–35 in solution satisfactorily reproduce experimental observation, and indicate the preference of forming β-sheet and random coil structure for Aβ25–35 in D2O just as the results of cluster analysis suggested. These maps with secondary structural sensitivity and amino acid residue specificity open up a way for the interpretation of amide-I vibrations and show their potentials in the understanding of molecular structure of polypeptides in solution.

We also recommend Trading Suppliers and Manufacturers of peptide T amide (cas 113021-67-3). Pls Click Website Link as below: cas 113021-67-3 suppliers

Prev:6-Methoxy-indanone derivatives as potential probes for β-amyloid plaques in Alzheimer's disease
Next:Potential roles for glucagon-like peptide-17–36 amide and cholecystokinin in anorectic response to the trichothecene mycotoxin T-2 toxin)