Parity-Violation Energy of Biomolecules—IV: Protein Secondary Structure

• DOI: 10.1007/s11084-010-9229-7
• Publication Date: 2010-12-15T18:43:55Z
• Authors: Francesco Faglioni; Inmaculada García...
• Keywords: Homochirality; Parity (physics); Biomolecule

The parity-violation energy difference between enantiomeric forms of the same amino acid sequence, from the amyloid β-peptide involved in Alzheimer's disease, in both α-helix and β-sheet configurations, is investigated with ab-initio techniques. To this end, we develop an extension of the N2 computational scheme that selectively includes neighboring amino acids to preserve the relevant H-bonds. In agreement with previous speculations, it is found that the helical α structure is associated with larger parity-violation energy differences than the corresponding β form. Implications for the evolution of biological homochirality are discussed as well as the relative importance of various effects in determining the parity-violation energy.