Solution Structure of Conomarphin, a Novel Conopeptide Containing D-Amino Acid at pH 5 |
| |
Authors: | Feijuan Huang Baohuai Wang |
| |
Institution: | a Department of Chemistry, Renmin University of China, Beijing 100872, P. R. China b Institute of Physical Chemistry, Peking University, Beijing 100871, P. R. China |
| |
Abstract: | Conomarphin, a novel conopeptide containing D-amino acid, was identified from the venom of Conus marmoreus and classified into M-superfamily of conotoxin. In this article, we reported the 3D structure of conomarphin at pH 5 determined using 2D 1H NMR method in aqueous solution. Twenty converged structures of this peptide were obtained based on 205 distance constraints, 8 dihedral angle constraints, and 2 hydrogen bond constraints. The root mean square deviation (RMSD) values of the backbone atoms were (0.074±0.029) nm. The refined structure of conomarphin at pH 5 contains a short 310-helix at C-terminal of the peptide. It was also characterized by a loose loop centered at Ala6. Comparison of structural and electrostatic potential between conomarphin at pH 3 and pH 5 were presented. Although the solution structure of conomarphin at pH 5 shared part of the same secondary structure element with the structure of conomarphin at pH 3, it adopted a distinctive backbone conformation with the overall molecule resembling a “flexual arm” when viewed from the front. Structural differences implied that this conopeptide was rather pH sensitive and its bioactivity in vivo might be related to the acidity. |
| |
Keywords: | Conomarphin Conopeptide D-phenylalanine NMR solution structure pH sensitive |
本文献已被 ScienceDirect 等数据库收录! |
|