1JTI

Loop-inserted Structure of P1-P1' Cleaved Ovalbumin Mutant R339T

1JTI の概要

• エントリーDOI: 10.2210/pdb1jti/pdb
• 分子名称: Ovalbumin (2 entities in total)
• 機能のキーワード: ovalbumin, loop insertion, non-inhibitory serpin, allergen
• 由来する生物種: Gallus gallus (chicken)
• 細胞内の位置: Secreted: P01012
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 85531.70

構造登録者

Yamasaki, M.,Arii, Y.,Mikami, B.,Hirose, M. (登録日: 2001-08-21, 公開日: 2001-09-05, 最終更新日: 2024-10-30)

主引用文献

Yamasaki, M.,Arii, Y.,Mikami, B.,Hirose, M.
Loop-inserted and thermostabilized structure of P1-P1' cleaved ovalbumin mutant R339T.
J.Mol.Biol., 315:113-120, 2002

PubMed Abstract: Ovalbumin is a member of a superfamily of serine proteinase inhibitors, known as the serpins. It is, however, non-inhibitory towards serine proteinases, and lacks the loop insertion mechanism common to the serpins due to unknown structural factors. Mutant ovalbumin, R339T, in which the P14 hinge residue is replaced, was produced and analyzed for its thermostability and three-dimensional structure. Differential scanning calorimetry revealed that the mutant ovalbumin, but not the wild-type protein, undergoes a marked thermostabilization (DeltaT(m)=15.8 degrees C) following the P1-P1' cleavage. Furthermore, the crystal structure, solved at 2.3 A resolution, clearly proved that the P1-P1' cleaved form assumes the fully loop-inserted conformation as seen in serpin that possess inhibitory activity. We therefore conclude that ovalbumin acquires the structural transition mechanism into the loop-inserted, thermostabilized form by the single hinge mutation. The mutant protein does not, however, possess inhibitory activity. The solved structure displays the occurrence of specific interactions that may prevent the smooth motion, relative to sheet A, of helices E and F and of the loop that follows helix F. These observations provide crucial insights into the question why R339T is still non-inhibitory.

PubMed: 11779232
DOI: 10.1006/jmbi.2001.5056

実験手法

X-RAY DIFFRACTION (2.3 Å)