3M7Q

Crystal structure of recombinant Kunitz Type serine protease Inhibitor-1 from the Caribbean sea anemone stichodactyla helianthus in complex with bovine pancreatic trypsin

3M7Q の概要

• エントリーDOI: 10.2210/pdb3m7q/pdb
• 分子名称: Cationic trypsin, Kunitz-type proteinase inhibitor SHPI-1, PHOSPHATE ION, ... (4 entities in total)
• 機能のキーワード: trypsin-inhibitor complex, kunitz-type serine-protease inhibitor, digestion, disulfide bond, hydrolase, metal-binding, protease, secreted, serine protease, zymogen, nematocyst, protease inhibitor, serine protease inhibitor, hydrolase-hydrolase inhibitor complex, hydrolase/hydrolase inhibitor
• 由来する生物種: Stichodactyla helianthus (Carribean sea anemone); 詳細
• 細胞内の位置: Secreted, extracellular space: P00760; Secreted: P31713
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 30114.84

構造登録者

Garcia-Fernandez, R.,Redecke, L.,Pons, T.,Perbandt, M.,Gil, D.,Talavera, A.,Gonzalez, Y.,de los angeles Chavez, M.,Betzel, C. (登録日: 2010-03-17, 公開日: 2011-03-16, 最終更新日: 2024-11-27)

主引用文献

Garcia-Fernandez, R.,Pons, T.,Perbandt, M.,Valiente, P.A.,Talavera, A.,Gonzalez-Gonzalez, Y.,Rehders, D.,Chavez, M.A.,Betzel, C.,Redecke, L.
Structural insights into serine protease inhibition by a marine invertebrate BPTI Kunitz-type inhibitor.
J.Struct.Biol., 180:271-279, 2012

PubMed Abstract: Proteins isolated from marine invertebrates are frequently characterized by exceptional structural and functional properties. ShPI-1, a BPTI Kunitz-type inhibitor from the Caribbean Sea anemone Stichodactyla helianthus, displays activity not only against serine-, but also against cysteine-, and aspartate proteases. As an initial step to evaluate the molecular basis of its activities, we describe the crystallographic structure of ShPI-1 in complex with the serine protease bovine pancreatic trypsin at 1.7Å resolution. The overall structure and the important enzyme-inhibitor interactions of this first invertebrate BPTI-like Kunitz-type inhibitor:trypsin complex remained largely conserved compared to mammalian BPTI-Kunitz inhibitor complexes. However, a prominent stabilizing role within the interface was attributed to arginine at position P3. Binding free-energy calculations indicated a 10-fold decrease for the inhibitor affinity against trypsin, if the P3 residue of ShPI-1 is mutated to alanine. Together with the increased role of Arg(11) at P3 position, slightly reduced interactions at the prime side (Pn') of the primary binding loop and at the secondary binding loop of ShPI-1 were detected. In addition, the structure provides important information for site directed mutagenesis to further optimize the activity of rShPI-1A for biotechnological applications.

PubMed: 22975140
DOI: 10.1016/j.jsb.2012.08.009

実験手法

X-RAY DIFFRACTION (1.7 Å)