We study the conformational dependence of circular dichroism (CD) spectra of amino acid molecules by means of an efficient ab initio DFT approach which is free from the typical gauge invariance issues arising with the use of localized basis sets and/or real-space grids. We analyze the dependence of the chiroptical spectra on the backbone dihedrals in the specific case of alanine and consider the role of side chain degrees of freedom at the examples of leucine, phenylalanine, and serine, whose side chains have different physicochemical properties. The results allow one to identify the most diagnostic regions of the CD spectra and to critically compare the conformations which match the experimental CD data with conformations extracted from the rotamer library. The inclusion of a solvation shell of explicit water molecules and its effect on the CD spectrum are analyzed at the example of alanine.

Conformational dependence of the circular dichroism spectra of single amino acids from plane-waves-based density functional theory calculations / E. Molteni, G. Onida, G. Tiana. - In: JOURNAL OF PHYSICAL CHEMISTRY. B, CONDENSED MATTER, MATERIALS, SURFACES, INTERFACES & BIOPHYSICAL. - ISSN 1520-6106. - 119:14(2015 Apr 09), pp. 4803-4811. [10.1021/jp5118568]

Conformational dependence of the circular dichroism spectra of single amino acids from plane-waves-based density functional theory calculations

E. Molteni
Primo
;
G. Onida
Secondo
;
G. Tiana
Ultimo
2015

Abstract

We study the conformational dependence of circular dichroism (CD) spectra of amino acid molecules by means of an efficient ab initio DFT approach which is free from the typical gauge invariance issues arising with the use of localized basis sets and/or real-space grids. We analyze the dependence of the chiroptical spectra on the backbone dihedrals in the specific case of alanine and consider the role of side chain degrees of freedom at the examples of leucine, phenylalanine, and serine, whose side chains have different physicochemical properties. The results allow one to identify the most diagnostic regions of the CD spectra and to critically compare the conformations which match the experimental CD data with conformations extracted from the rotamer library. The inclusion of a solvation shell of explicit water molecules and its effect on the CD spectrum are analyzed at the example of alanine.
Circular Dichroism; Density Functional Theory; Aminoacids; Optical Properties
Settore FIS/03 - Fisica della Materia
Settore FIS/07 - Fisica Applicata(Beni Culturali, Ambientali, Biol.e Medicin)
Settore BIO/11 - Biologia Molecolare
9-apr-2015
Article (author)
File in questo prodotto:
File Dimensione Formato  
jp5118568.pdf

accesso riservato

Tipologia: Publisher's version/PDF
Dimensione 1.31 MB
Formato Adobe PDF
1.31 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2434/270621
Citazioni
  • ???jsp.display-item.citation.pmc??? 1
  • Scopus 10
  • ???jsp.display-item.citation.isi??? 10
social impact