2RQ2

The solution structure of the N-terminal fragment of big defensin

2RQ2 の概要

• エントリーDOI: 10.2210/pdb2rq2/pdb
• NMR情報: BMRB: 11072
• 分子名称: Big defensin (1 entity in total)
• 機能のキーワード: antimicrobial peptide, antibiotic, antimicrobial, fungicide, secreted
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 2887.33

構造登録者

Kouno, T.,Mizuguchi, M.,Aizawa, T.,Shinoda, H.,Demura, M.,Kawabata, S.,Kawano, K. (登録日: 2009-01-07, 公開日: 2009-08-25, 最終更新日: 2024-05-15)

主引用文献

Kouno, T.,Mizuguchi, M.,Aizawa, T.,Shinoda, H.,Demura, M.,Kawabata, S.,Kawano, K.
A novel beta-defensin structure: big defensin changes its N-terminal structure to associate with the target membrane
Biochemistry, 48:7629-7635, 2009

PubMed Abstract: Big defensin is a 79-residue peptide derived from hemocytes of the Japanese horseshoe crab. The amino acid sequence of big defensin is divided into an N-terminal hydrophobic domain and a C-terminal cationic domain, which are responsible for antimicrobial activities against Gram-positive and -negative bacteria, respectively. The N-terminal domain of big defensin forms a unique globular conformation with two alpha-helices and a parallel beta-sheet, while the C-terminal domain adopts a beta-defensin-like fold. Although our previous study implied that big defensin changes its N-terminal structure in a micellar environment, due to the poor quality of the NMR spectra it remained to be resolved whether the N-terminal domain adopts any structure in the presence of micelles. In this analysis, we successfully determined the structure of the N-terminal fragment of big defensin in a micellar solution, showing that the fragment peptide forms a single alpha-helix structure. Moreover, NMR experiments using paramagnetic probes revealed that the N-terminal domain of big defensin penetrates into the micelle with a dipping at the N-terminal edge of the alpha-helix. Here, we propose a model for how big defensin associates with the target membrane.

PubMed: 19588912
DOI: 10.1021/bi900756y

実験手法

SOLUTION NMR