1F32

CRYSTAL STRUCTURE OF ASCARIS PEPSIN INHIBITOR-3

1F32 の概要

• エントリーDOI: 10.2210/pdb1f32/pdb
• 関連するPDBエントリー: 1F34
• 分子名称: MAJOR PEPSIN INHIBITOR PI-3 (2 entities in total)
• 機能のキーワード: proteinase inhibitor, hydrolase inhibitor
• 由来する生物種: Ascaris suum (pig roundworm)
• 細胞内の位置: Secreted: P19400
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 16411.69

構造登録者

Ng, K.K.,Petersen, J.F.,Cherney, M.M.,Garen, C.,James, M.N. (登録日: 2000-05-31, 公開日: 2001-02-01, 最終更新日: 2024-11-13)

主引用文献

Ng, K.K.,Petersen, J.F.,Cherney, M.M.,Garen, C.,Zalatoris, J.J.,Rao-Naik, C.,Dunn, B.M.,Martzen, M.R.,Peanasky, R.J.,James, M.N.
Structural basis for the inhibition of porcine pepsin by Ascaris pepsin inhibitor-3.
Nat.Struct.Biol., 7:653-657, 2000

PubMed Abstract: The three-dimensional structures of pepsin inhibitor-3 (PI-3) from Ascaris suum and of the complex between PI-3 and porcine pepsin at 1. 75 A and 2.45 A resolution, respectively, have revealed the mechanism of aspartic protease inhibition by this unique inhibitor. PI-3 has a new fold consisting of two domains, each comprising an antiparallel beta-sheet flanked by an alpha-helix. In the enzyme-inhibitor complex, the N-terminal beta-strand of PI-3 pairs with one strand of the 'active site flap' (residues 70-82) of pepsin, thus forming an eight-stranded beta-sheet that spans the two proteins. PI-3 has a novel mode of inhibition, using its N-terminal residues to occupy and therefore block the first three binding pockets in pepsin for substrate residues C-terminal to the scissile bond (S1'-S3'). The molecular structure of the pepsin-PI-3 complex suggests new avenues for the rational design of proteinaceous aspartic proteinase inhibitors.

PubMed: 10932249
DOI: 10.1038/77950

実験手法

X-RAY DIFFRACTION (1.75 Å)