4AAZ

X-ray structure of Nicotiana alata Defensin 1 NaD1

4AAZ の概要

• エントリーDOI: 10.2210/pdb4aaz/pdb
• 関連するPDBエントリー: 4AB0
• 分子名称: FLOWER-SPECIFIC DEFENSIN, 1,2-ETHANEDIOL, PHOSPHATE ION, ... (4 entities in total)
• 機能のキーワード: antimicrobial protein, innate immunity
• 由来する生物種: NICOTIANA ALATA (PERSIAN TOBACCO)
• 細胞内の位置: Secreted (By similarity): Q8GTM0
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 11036.07

構造登録者

Lay, F.T.,Mills, G.D.,Hulett, M.D.,Kvansakul, M. (登録日: 2011-12-06, 公開日: 2012-04-25, 最終更新日: 2024-11-06)

主引用文献

Lay, F.T.,Mills, G.D.,Poon, I.K.,Cowieson, N.P.,Kirby, N.,Baxter, A.A.,Van Der Weerden, N.L.,Dogovski, C.,Perugini, M.A.,Anderson, M.A.,Kvansakul, M.,Hulett, M.D.
Dimerization of Plant Defensin Nad1 Enhances its Antifungal Activity.
J.Biol.Chem., 287:19961-, 2012

PubMed Abstract: The plant defensin, NaD1, from the flowers of Nicotiana alata, is a member of a family of cationic peptides that displays growth inhibitory activity against several filamentous fungi, including Fusarium oxysporum. The antifungal activity of NaD1 has been attributed to its ability to permeabilize membranes; however, the molecular basis of this function remains poorly defined. In this study, we have solved the structure of NaD1 from two crystal forms to high resolution (1.4 and 1.58 Å, respectively), both of which contain NaD1 in a dimeric configuration. Using protein cross-linking experiments as well as small angle x-ray scattering analysis and analytical ultracentrifugation, we show that NaD1 forms dimers in solution. The structural studies identified Lys(4) as critical in formation of the NaD1 dimer. This was confirmed by site-directed mutagenesis of Lys(4) that resulted in substantially reduced dimer formation. Significantly, the reduced ability of the Lys(4) mutant to dimerize correlated with diminished antifungal activity. These data demonstrate the importance of dimerization in NaD1 function and have implications for the use of defensins in agribiotechnology applications such as enhancing plant crop protection against fungal pathogens.

PubMed: 22511788
DOI: 10.1074/JBC.M111.331009

実験手法

X-RAY DIFFRACTION (1.4 Å)