Datta, S and Shamala, N and Gurunath, R and Balaram, P (1996) Observation of a mixed antiparallel and parallel beta-sheet motif in the crystal structure of Boc-Ala-Ile-Aib-OMe. In: International Journal of Peptide & Protein Research, 48 (3). pp. 209-214.
Full text not available from this repository. (Request a copy)Abstract
A diastereomeric mixture of the tripeptide Boc-Ala-Ile-Aib-OMe crystallized in the space group P1 from CH3OH/H2O. The unit cell parameters are a = 10.593(2) A, b = 14.377(3) A, c = 17.872(4) A, alpha = 104.41(2) degrees, beta = 90.55(2) degrees, gamma = 106.91(2) degrees, V = 2512.4 A3, Z = 4. X-Ray crystallographic studies show the presence of four molecules in the asymmetric unit consisting of two pairs of diastereomeric peptides, Boc-L-Ala-L-Ile-Aib-OMe and Boc-L-Ala-D-Ile-Aib-OMe. The four molecules in the asymmetric unit form a rarely found mixed antiparallel and parallel beta-sheet hydrogen bond motif. The Ala and (L,D)-Ile residues in all the four molecules adopt the extended conformations, while the phi, psi values of the Aib residues are in the right-handed helical region. In one of the molecules the Ile sidechain adopts the unusual gauche conformation about the C beta-C gamma bond.
Item Type: | Journal Article |
---|---|
Publication: | International Journal of Peptide & Protein Research |
Publisher: | Munksgaard int pub ltd |
Additional Information: | Copyright of this article belongs to Munksgaard int pub ltd. |
Department/Centre: | Division of Biological Sciences > Molecular Biophysics Unit Division of Physical & Mathematical Sciences > Physics |
Date Deposited: | 22 Jan 2010 06:39 |
Last Modified: | 22 Jan 2010 06:39 |
URI: | http://eprints.iisc.ac.in/id/eprint/24726 |
Actions (login required)
View Item |