Conformations peptide fragment studies

The conformational angles derived in this study are unusual values in the Ramachandran map because these maps are based on conformational energy calculations for molecules as N-acetyl-alanine-N -methyl amide, which do not incorporate charged groups and thus will reproduce an uncharged peptide fragment better than an aqueous solution of a zwitterionic peptide. 

The predicted structures spurred a number of both experimental and simulation studies to test the predictions and to address the conformational properties of small peptide fragments of PrP. In particular, focus was place on the predicted H1-H4 helices and their conformational properties under a variety of conditions. Although the properties of fragments can often be misleading and have little in common with the properties of the segment in the context of the full-length protein. 

A fusogenic Alzheimer s peptide fragment was studied in interaction with lipid bilayers using solid-state NMR in order to study its secondary structure, dynamics, and specific interaction with phosphatidyl ethanolamine polar heads.The chemical shifts of alanine methyl isotropic carbon were determined by MAS NMR, and they clearly demonstrated that the major form of the peptide equilibrated in membrane was not in a helical conformation. NMR was also used to probe dynamics of lipid bilayers. In addition, NMR... 

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