6ANN

Structure of cyclic D-Leu-N-methyl-D-Phe-2-Abz-D-Ala at 0.76 Angstrom

6ANN の概要

• エントリーDOI: 10.2210/pdb6ann/pdb
• 関連するPDBエントリー: 6ANM
• 分子名称: cyclic DLE-ZAE-BE2-DAL, ETHANOL (3 entities in total)
• 機能のキーワード: unnatural amino acid, peptidomimetic beta-turn, d-amino acid, tetrapeptide, cyclic peptide, de novo protein
• 由来する生物種: synthetic construct
• タンパク質・核酸の鎖数: 5
• 化学式量合計: 2551.06

構造登録者

Cameron, A.J.,Sarojini, V.,Squire, C.J. (登録日: 2017-08-14, 公開日: 2017-11-15, 最終更新日: 2023-11-15)

主引用文献

Cameron, A.J.,Squire, C.J.,Edwards, P.J.B.,Harjes, E.,Sarojini, V.
Crystal and NMR Structures of a Peptidomimetic beta-Turn That Provides Facile Synthesis of 13-Membered Cyclic Tetrapeptides.
Chem Asian J, 12:3195-3202, 2017

PubMed Abstract: Herein we report the unique conformations adopted by linear and cyclic tetrapeptides (CTPs) containing 2-aminobenzoic acid (2-Abz) in solution and as single crystals. The crystal structure of the linear tetrapeptide H N-d-Leu-d-Phe-2-Abz-d-Ala-COOH (1) reveals a novel planar peptidomimetic β-turn stabilized by three hydrogen bonds and is in agreement with its NMR structure in solution. While CTPs are often synthetically inaccessible or cyclize in poor yield, both 1 and its N-Me-d-Phe analogue (2) adopt pseudo-cyclic frameworks enabling near quantitative conversion to the corresponding CTPs 3 and 4. The crystal structure of the N-methylated peptide (4) is the first reported for a CTP containing 2-Abz and reveals a distinctly planar 13-membered ring, which is also evident in solution. The N-methylation of d-Phe results in a peptide bond inversion compared to the conformation of 3 in solution.

PubMed: 29098772
DOI: 10.1002/asia.201701422

実験手法

X-RAY DIFFRACTION (0.76 Å)