4DDN

Structure analysis of a wound-inducible lectin ipomoelin from sweet potato

4DDN の概要

• エントリーDOI: 10.2210/pdb4ddn/pdb
• 関連するPDBエントリー: 3R50 3R51 3R52
• 分子名称: Ipomoelin, methyl alpha-D-galactopyranoside (3 entities in total)
• 機能のキーワード: beta prism, carbohydrate binding protein, carbohydrate/sugar binding, sugar binding protein
• 由来する生物種: Ipomoea batatas (batate)
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 70158.41

構造登録者

Chang, W.C.,Liu, K.L.,Jeng, S.T.,Hsu, F.C.,Cheng, Y.S. (登録日: 2012-01-19, 公開日: 2012-08-01, 最終更新日: 2023-09-13)

主引用文献

Chang, W.C.,Liu, K.L.,Hsu, F.C.,Jeng, S.T.,Cheng, Y.S.
Ipomoelin, a jacalin-related lectin with a compact tetrameric association and versatile carbohydrate binding properties regulated by its N terminus.
Plos One, 7:e40618-e40618, 2012

PubMed Abstract: Many proteins are induced in the plant defense response to biotic stress or mechanical wounding. One group is lectins. Ipomoelin (IPO) is one of the wound-inducible proteins of sweet potato (Ipomoea batatas cv. Tainung 57) and is a Jacalin-related lectin (JRL). In this study, we resolved the crystal structures of IPO in its apo form and in complex with carbohydrates such as methyl α-D-mannopyranoside (Me-Man), methyl α-D-glucopyranoside (Me-Glc), and methyl α-D-galactopyranoside (Me-Gal) in different space groups. The packing diagrams indicated that IPO might represent a compact tetrameric association in the JRL family. The protomer of IPO showed a canonical β-prism fold with 12 strands of β-sheets but with 2 additional short β-strands at the N terminus. A truncated IPO (ΔN10IPO) by removing the 2 short β-strands of the N terminus was used to reveal its role in a tetrameric association. Gel filtration chromatography confirmed IPO as a tetrameric form in solution. Isothermal titration calorimetry determined the binding constants (K(A)) of IPO and ΔN10IPO against various carbohydrates. IPO could bind to Me-Man, Me-Glc, and Me-Gal with similar binding constants. In contrast, ΔN10IPO showed high binding ability to Me-Man and Me-Glc but could not bind to Me-Gal. Our structural and functional analysis of IPO revealed that its compact tetrameric association and carbohydrate binding polyspecificity could be regulated by the 2 additional N-terminal β-strands. The versatile carbohydrate binding properties of IPO might play a role in plant defense.

PubMed: 22808208
DOI: 10.1371/journal.pone.0040618

実験手法

X-RAY DIFFRACTION (1.9 Å)