7WIO

NMR structure of N-terminal domain of Triconephila clavipes of major ampullate spidroin 1

7WIO の概要

• エントリーDOI: 10.2210/pdb7wio/pdb
• 分子名称: Major ampullate spidroin 1A (1 entity in total)
• 機能のキーワード: dragline spider silk, spider silk assembly, ph regulation, structural protein
• 由来する生物種: Trichonephila clavipes
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 14499.00

構造登録者

Oktaviani, N.A.,Malay, A.D.,Matsugami, A.,Hayashi, F.,Numata, K. (登録日: 2022-01-04, 公開日: 2023-03-15, 最終更新日: 2024-05-15)

主引用文献

Oktaviani, N.A.,Malay, A.D.,Matsugami, A.,Hayashi, F.,Numata, K.
Unusual p K a Values Mediate the Self-Assembly of Spider Dragline Silk Proteins.
Biomacromolecules, 24:1604-1616, 2023

PubMed Abstract: Spider dragline silk is a remarkably tough biomaterial and composed primarily of spidroins MaSp1 and MaSp2. During fiber self-assembly, the spidroin N-terminal domains (NTDs) undergo rapid dimerization in response to a pH gradient. However, obtaining a detailed understanding of this mechanism has been hampered by a lack of direct evidence regarding the protonation states of key ionic residues. Here, we elucidated the solution structures of MaSp1 and MaSp2 NTDs from and determined the experimental pa values of conserved residues involved in dimerization using NMR. Surprisingly, we found that the Asp40 located on an acidic cluster protonates at an unusually high pH (∼6.5-7.1), suggesting the first step in the pH response. Then, protonation of Glu119 and Glu79 follows, with ps above their intrinsic values, contributing toward stable dimer formation. We propose that exploiting the atypical p values is a strategy to achieve tight spatiotemporal control of spider silk self-assembly.

PubMed: 36990448
DOI: 10.1021/acs.biomac.2c01344

実験手法

SOLUTION NMR