| Autor: |
Sharma GV; Organic and Biomolecular Chemistry Division, CSIR-Indian Institute of Chemical Technology, Hyderabad-500 007, India., Reddy NY, Ravi R, Sreenivas B, Sridhar G, Chatterjee D, Kunwar AC, Hofmann HJ |
| Jazyk: |
angličtina |
| Zdroj: |
Organic & biomolecular chemistry [Org Biomol Chem] 2012 Dec 14; Vol. 10 (46), pp. 9191-203. Date of Electronic Publication: 2012 Oct 22. |
| DOI: |
10.1039/c2ob26615f |
| Abstrakt: |
C-linked carbo-β(2)-amino acids (β(2)-Caa), a new class of β-amino acid with a carbohydrate side chain having d-xylo configuration, were prepared from d-glucose. The main idea behind the design of the new β-amino acids was to move the steric strain of the bulky carbohydrate side chain from the Cβ- to the Cα-carbon atom and to explore its influence on the folding propensities in peptides with alternating (R)- and (S)-β(2)-Caas. The tetra- and hexapeptides derived were studied employing NMR (in CDCl(3)), CD, and molecular dynamics simulations. The β(2)-peptides of the present study form left-handed 12/10- and 10/12-mixed helices independent of the order of the alternating chiral amino acids in the sequence and result in a new motif. These results differ from earlier findings on β(3)-peptides of the same design, containing a carbohydrate side chain with d-xylo configuration, which form exclusively right-handed 12/10-mixed helices. Quantum chemical calculations employing ab initio MO theory suggest the side chain chirality as an important factor for the observed definite left- or right-handedness of the helices in the β(2)- and β(3)-peptides. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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