PDBsum entry 4doq

Hydrolase/hydrolase inhibitor

PDB id: 4doq

Contents

Protein chains

221 a.a.

47 a.a.

Ligands

XPE

SO4 ×7

P6G

Metals

_CA ×3

Waters ×516

PDB id:

4doq

Name:

Hydrolase/hydrolase inhibitor

Title:

Crystal structure of the complex of porcine pancreatic trypsin with 1/2slpi

Structure:

Trypsin. Chain: a, c, e. Antileukoproteinase. Chain: b, d. Fragment: c-terminal domain. Synonym: secretory leukocyte protease inhibitor. Engineered: yes

Source:

Sus scrofa. Pig. Organism_taxid: 9823. Tissue: pancreas. Synthetic: yes. Homo sapiens. Human. Organism_taxid: 9606. Other_details: this sequence occurs naturally in humans.

Resolution:

2.00Å R-factor: 0.190 R-free: 0.242

Authors:

K.Fukushima,M.Takimoto-Kamimura

Key ref:

K.Fukushima et al. (2013). Structure basis 1/2SLPI and porcine pancreas trypsin interaction. J Synchrotron Radiat, 20, 943-947. PubMed id: 24121345 DOI: 10.1107/S090904951302133X

Date:

10-Feb-12 Release date: 14-Aug-13

Protein chains

P00761  (TRYP_PIG) -  Trypsin from Sus scrofa

Seq: 231 a.a.

Struc: 221 a.a.

Protein chains

P03973  (SLPI_HUMAN) -  Antileukoproteinase from Homo sapiens

Seq: 132 a.a.

Struc: 47 a.a.

Enzyme reactions

• Enzyme class: Chains A, C, E: E.C.3.4.21.4 - trypsin.
• Reaction: Preferential cleavage: Arg-|-Xaa, Lys-|-Xaa.

DOI no: 10.1107/S090904951302133X

J Synchrotron Radiat 20:943-947 (2013)

PubMed id: 24121345

Structure basis 1/2SLPI and porcine pancreas trypsin interaction.

K.Fukushima, T.Kamimura, M.Takimoto-Kamimura.

ABSTRACT

SLPI (secretory leukocyte protease inhibitor) is a 107-residue protease inhibitor which inhibits various serine proteases, including elastase, cathepsin G, chymotrypsin and trypsin. SLPI is obtained as a multiple inhibitor in lung defense and in chronic airway infection. X-ray crystal structures have so far reported that they are full-length SLPIs with bovine α-chymotrypsin and 1/2SLPI (recombinant C-terminal domain of SLPI; Arg58-Ala107) with HNE (human neutrophil elastase). To understand the role of this multiple inhibitory mechanism, the crystal structure of 1/2SLPI with porcine pancreas trypsin was solved and the binding modes of two other complexes compared. The Leu residue surprisingly interacts with the S1 site of trypsin, as with chymotrypsin and elastase. The inhibitory mechanism of 1/2SLPI using the wide primary binding site contacts (from P2' to P5) with various serine proteases is discussed. These inhibitory mechanisms have been acquired in the evolution of the protection system for acute inflammatory diseases.