7BWY

Crystal structure of ice-binding protein from an Antarctic ascomycete, Antarctomyces psychrotrophicus.

7BWY の概要

• エントリーDOI: 10.2210/pdb7bwy/pdb
• 分子名称: Ice-binding protein isoform1a, GLYCEROL (3 entities in total)
• 機能のキーワード: beta-solenoid, right-handed beta-helix, antifreeze protein
• 由来する生物種: Antarctomyces psychrotrophicus
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 67426.66

構造登録者

Yamauchi, A.,Arai, T.,Kondo, H.,Tsuda, S. (登録日: 2020-04-16, 公開日: 2020-05-27, 最終更新日: 2023-11-29)

主引用文献

Yamauchi, A.,Arai, T.,Kondo, H.,Sasaki, Y.C.,Tsuda, S.
An Ice-Binding Protein from an Antarctic Ascomycete Is Fine-Tuned to Bind to Specific Water Molecules Located in the Ice Prism Planes.
Biomolecules, 10:-, 2020

PubMed Abstract: Many microbes that survive in cold environments are known to secrete ice-binding proteins (IBPs). The structure-function relationship of these proteins remains unclear. A microbial IBP denoted IBP was recently isolated from a cold-adapted fungus, . The present study identified an orbital illumination (prism ring) on a globular single ice crystal when soaked in a solution of fluorescent IBP, suggesting that IBP binds to specific water molecules located in the ice prism planes. In order to examine this unique ice-binding mechanism, we carried out X-ray structural analysis and mutational experiments. It appeared that IBP is made of 6-ladder β-helices with a triangular cross section that accompanies an "ice-like" water network on the ice-binding site. The network, however, does not exist in a defective mutant. IBP has a row of four unique hollows on the IBS, where the distance between the hollows (14.7 Å) is complementary to the oxygen atom spacing of the prism ring. These results suggest the structure of IBP is fine-tuned to merge with the ice-water interface of an ice crystal through its polygonal water network and is then bound to a specific set of water molecules constructing the prism ring to effectively halt the growth of ice.

PubMed: 32414092
DOI: 10.3390/biom10050759

実験手法

X-RAY DIFFRACTION (2.02 Å)