3AUP

Crystal structure of Basic 7S globulin from soybean

3AUP の概要

• エントリーDOI: 10.2210/pdb3aup/pdb
• 分子名称: Basic 7S globulin (2 entities in total)
• 機能のキーワード: pepsin-like fold, plant protein
• 由来する生物種: Glycine max (soybeans)
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 174946.72

構造登録者

Yoshizawa, T.,Shimizu, T.,Taichi, M.,Nishiuchi, Y.,Yamabe, M.,Shichijo, N.,Unzai, S.,Hirano, H.,Sato, M.,Hashimoto, H. (登録日: 2011-02-14, 公開日: 2011-04-27, 最終更新日: 2024-11-20)

主引用文献

Yoshizawa, T.,Shimizu, T.,Yamabe, M.,Taichi, M.,Nishiuchi, Y.,Shichijo, N.,Unzai, S.,Hirano, H.,Sato, M.,Hashimoto, H.
Crystal structure of basic 7S globulin, a xyloglucan-specific endo-beta-1,4-glucanase inhibitor protein-like protein from soybean lacking inhibitory activity against endo-beta-glucanase
Febs J., 278:1944-1954, 2011

PubMed Abstract: β-Linked glucans such as cellulose and xyloglucan are important components of the cell walls of most dicotyledonous plants. These β-linked glucans are constantly exposed to degradation by various endo-β-glucanases from pathogenic bacteria and fungi. To protect the cell wall from degradation by such enzymes, plants secrete proteinaceous endo-β-glucanases inhibitors, such as xyloglucan-specific endo-β-1,4-glucanase inhibitor protein (XEGIP) in tomato. XEGIPs typically inhibit xyloglucanase, a member of the glycoside hydrolase (GH)12 family. XEGIPs are also found in legumes, including soybean and lupin. To date, tomato XEGIP has been well studied, whereas XEGIPs from legumes are less well understood. Here, we determined the crystal structure of basic 7S globulin (Bg7S), a XEGIP from soybean, which represents the first three-dimensional structure of XEGIP. Bg7S formed a tetramer with pseudo-222 symmetry. Analytical centrifugation and size exclusion chromatography experiments revealed that the assembly of Bg7S in solution depended on pH. The structure of Bg7S was similar to that of a xylanase inhibitor protein from wheat (Tritinum aestivum xylanase inhibitor) that inhibits GH11 xylanase. Surprisingly, Bg7S lacked inhibitory activity against not only GH11 but also GH12 enzymes. In addition, we found that XEGIPs from azukibean, yardlongbean and mungbean also had no impact on the activity of either GH12 or GH11 enzymes, indicating that legume XEGIPs generally do not inhibit these enzymes. We reveal the structural basis of why legume XEGIPs lack this inhibitory activity. This study will provide significant clues for understanding the physiological role of Bg7S.

PubMed: 21457461
DOI: 10.1111/j.1742-4658.2011.08111.x

実験手法

X-RAY DIFFRACTION (1.91 Å)