8AN6

The Crystal structure of wt apo agroavidin - biotin complex

8AN6 の概要

• エントリーDOI: 10.2210/pdb8an6/pdb
• 関連するPDBエントリー: 8AMH
• 分子名称: Agroavidin, BIOTIN (3 entities in total)
• 機能のキーワード: biotin binding protein, avidin, biotin, high affinity systems, unknown function
• 由来する生物種: Rhizobium sp. AAP43
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 60202.38

構造登録者

Livnah, O.,Bana, J. (登録日: 2022-08-04, 公開日: 2023-04-12, 最終更新日: 2024-11-06)

主引用文献

Bana, J.,Warwar, J.,Bayer, E.A.,Livnah, O.
Self-assembly of a dimeric avidin into unique higher-order oligomers.
Febs J., 290:3563-3579, 2023

PubMed Abstract: The dimeric avidin family has been expanded in recent years to include many new members. All of them lack the intermonomeric Trp that plays a critical role in biotin-binding. Nevertheless, these new members of the avidins maintain the high affinity towards biotin. Additionally, all of the dimeric avidins share a very unique property: namely, the cylindrical oligomerization in the crystal structure. The newest member described here, agroavidin from the agrobacterium, Rhizobium sp. AAP43, shares their important structural features. However, the affinity of agroavidin towards biotin is lower than all other members of the avidin family, due to the presence of phenylalanine instead of a conserved tyrosine in the biotin-binding site. Mutating this phenylalanine into tyrosine regenerated the high affinity, which emphasizes the importance of this particular tyrosine residue. Another unique feature that distinguishes agroavidin from the other dimeric avidins is that it does not produce oligomers in its crystal structure. In order to understand the factors that promote oligomerization in dimeric avidins, we exchanged the C-terminal region of agroavidin with that of hoefavidin that produced octamers. This exchange resulted in a decamer rather than an octamer. This unusual outcome demonstrates the impact of the C-terminal region on the ability to produce oligomers. The decameric assembly of agroavidin expands the avidin-biotin toolbox even further and could well pave the path into new biotin-based technologies. Moreover, uncovering the factors that induce dimeric avidins into oligomeric assemblies may aid in better understanding the general molecular determinants that promote oligomerization.

PubMed: 36853192
DOI: 10.1111/febs.16764

実験手法

X-RAY DIFFRACTION (1.9 Å)