4D8M

Crystal structure of Bacillus thuringiensis Cry5B nematocidal toxin

4D8M の概要

• エントリーDOI: 10.2210/pdb4d8m/pdb
• 分子名称: Pesticidal crystal protein cry5Ba (2 entities in total)
• 機能のキーワード: glycolipid binding, lipid binding protein, structural genomics, berkeley structural genomics center, bsgc
• 由来する生物種: Bacillus thuringiensis
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 66088.07

構造登録者

Fan, H.,Hu, Y.,Aroian, R.V.,Ghosh, P.,Berkeley Structural Genomics Center (BSGC) (登録日: 2012-01-10, 公開日: 2012-12-19, 最終更新日: 2024-11-20)

主引用文献

Hui, F.,Scheib, U.,Hu, Y.,Sommer, R.J.,Aroian, R.V.,Ghosh, P.
Structure and Glycolipid Binding Properties of the Nematicidal Protein Cry5B.
Biochemistry, 51:9911-9921, 2012

PubMed Abstract: Crystal (Cry) proteins are globally used in agriculture as proteinaceous insecticides. They have also been recently recognized to have great potential as anthelmintic agents in targeting parasitic roundworms (e.g., hookworms). The most extensively characterized of the anthelmintic Cry proteins is Cry5B. We report here the 2.3 Å resolution structure of the proteolytically activated form of Cry5B. This structure, which is the first for a nematicidal Cry protein, shows the familiar three-domain arrangement seen in insecticidal Cry proteins. However, domain II is unusual in that it more closely resembles a banana lectin than it does other Cry proteins. This result is consistent with the fact that the receptor for Cry5B consists of a set of invertebrate-specific glycans (attached to lipids) and also suggests that domain II is important for receptor binding. We found that not only galactose but also N-acetylgalactosamine (GalNAc) is an efficient competitor for binding between Cry5B and glycolipids. GalNAc is one of the core arthroseries tetrasaccharides of the Cry5B receptor and galactose an antennary sugar that emanates from this core. These and prior data suggest that the minimal binding determinant for Cry5B consists of a core GalNAc and two antennary galactoses. Lastly, the protoxin form of Cry5B was found to bind nematode glycolipids with a specificity equal to that of activated Cry5B, but with lower affinity. This suggests that the initial binding of Cry5B protoxin to glycolipids can be stabilized at the nematode cell surface by proteolysis. These results lay the groundwork for the design of effective Cry5B-based anthelmintics.

PubMed: 23150986
DOI: 10.1021/bi301386q

実験手法

X-RAY DIFFRACTION (2.3 Å)