Počet záznamů: 1
Three Types of Induced Tryptophan Optical Activity Compared in Model Dipeptides: Theory and Experiment
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SYSNO ASEP 0383282 Druh ASEP J - Článek v odborném periodiku Zařazení RIV J - Článek v odborném periodiku Poddruh J Článek ve WOS Název Three Types of Induced Tryptophan Optical Activity Compared in Model Dipeptides: Theory and Experiment Tvůrce(i) Hudecová, Jana (UOCHB-X) RID, ORCID
Horníček, Jan (UOCHB-X)
Buděšínský, Miloš (UOCHB-X) RID, ORCID
Šebestík, Jaroslav (UOCHB-X) RID, ORCID
Šafařík, Martin (UOCHB-X) ORCID
Zhang, G. (US)
Keiderling, T. A. (US)
Bouř, Petr (UOCHB-X) RID, ORCIDCelkový počet autorů 8 Zdroj.dok. ChemPhysChem. - : Wiley - ISSN 1439-4235
Roč. 13, č. 11 (2012), s. 2748-2760Poč.str. 13 s. Jazyk dok. eng - angličtina Země vyd. DE - Německo Klíč. slova circular dichroism ; conformation analysis ; density functional calculations ; Raman spectroscopy ; peptides Vědní obor RIV CF - Fyzikální chemie a teoretická chemie CEP GAP208/11/0105 GA ČR - Grantová agentura ČR LH11033 GA MŠMT - Ministerstvo školství, mládeže a tělovýchovy CEZ AV0Z40550506 - UOCHB-X (2005-2011) UT WOS 000306900700021 DOI 10.1002/cphc.201200201 Anotace The tryptophan (Trp) aromatic residue in chiral matrices often exhibits a large optical activity and thus provides valuable structural information. However, it can also obscure spectral contributions from other peptide parts. To better understand the induced chirality, electronic circular dichroism (ECD), vibrational circular dichroism (VCD), and Raman optical activity (ROA) spectra of Trp-containing cyclic dipeptides c-(Trp-X) (where X=Gly, Ala, Trp, Leu, nLeu, and Pro) are analyzed on the basis of experimental spectra and density functional theory (DFT) computations. The results provide valuable insight into the molecular conformational and spectroscopic behavior of Trp. Whereas the ECD is dominated by Trp pi-pi transitions, VCD is dominated by the amide modes, well separated from minor Trp contributions. The ROA signal is the most complex. However, an ROA marker band at 1554 cm-1 indicates the local chi2 angle value in this residue, in accordance with previous theoretical predictions. The spectra and computations also indicate that the peptide ring is nonplanar, with a shallow potential so that the nonplanarity is primarily induced by the side chains. Dispersion-corrected DFT calculations provide better results than plain DFT, but comparison with experiment suggests that they overestimate the stability of the folded conformers. Molecular dynamics simulations and NMR results also confirm a limited accuracy of the dispersion-DFT model in nonaqueous solvents. Combination of chiral spectroscopies with theoretical analysis thus significantly enhances the information that can be obtained from the induced chirality of the Trp aromatic residue. Pracoviště Ústav organické chemie a biochemie Kontakt asep@uochb.cas.cz ; Kateřina Šperková, Tel.: 232 002 584 ; Jana Procházková, Tel.: 220 183 418 Rok sběru 2013
Počet záznamů: 1