PDBsum entry 2rel

Serine protease inhibitor

PDB id: 2rel

Contents

Protein chain

57 a.a. *

* Residue conservation analysis

PDB id:

2rel

Name:

Serine protease inhibitor

Title:

Solution structure of r-elafin, a specific inhibitor of elastase, nmr, 11 structures

Structure:

R-elafin. Chain: a. Engineered: yes

Source:

Homo sapiens. Human. Organism_taxid: 9606. Expressed in: escherichia coli. Expression_system_taxid: 562. Other_details: the polypeptide may be obtained by expression using plasmidic expression systems in hosts such as escherichia coli and yeast, the polypeptide being also obtainable from psoriatic plaques. Patent number 5,464,822 date of patent nov. 7, 1995 by christophers

NMR struc:

11 models

Authors:

C.Francart,M.Dauchez,A.J.P.Alix,G.Lippens

Key ref:

C.Francart et al. (1997). Solution structure of R-elafin, a specific inhibitor of elastase. J Mol Biol, 268, 666-677. PubMed id: 9171290 DOI: 10.1006/jmbi.1997.0983

Date:

01-Apr-97 Release date: 07-Jul-97

Supersedes:

1rel

Protein chain

P19957  (ELAF_HUMAN) -  Elafin from Homo sapiens

Seq: 117 a.a.

Struc: 57 a.a.

DOI no: 10.1006/jmbi.1997.0983

J Mol Biol 268:666-677 (1997)

PubMed id: 9171290

Solution structure of R-elafin, a specific inhibitor of elastase.

C.Francart, M.Dauchez, A.J.Alix, G.Lippens.

ABSTRACT

The solution structure of r-elafin, a specific elastase inhibitor, has been determined using NMR spectroscopy. Characterized by a flat core and a flexible N-terminal extremity, the three-dimensional structure is formed by a central twisted beta-hairpin accompanied by two external segments linked by the proteinase binding loop. A cluster of three disulfide bridges connects the external segments to the central beta-sheet and a single fourth disulfide bridge links the binding loop to the central beta-turn. The same spatial distribution of disulfide bridges can be observed in both domains of the secretory leukocyte protease inhibitor (SLPI), another elastase inhibitor. The structural homology between r-elafin and the C-terminal domain of SLPI confirms the former as a second member of the chelonianin family of proteinase inhibitors. Based on the homology between the two proteins and recent results obtained for elastase binding mutants of the bovine pancreatic trypsin inhibitor (BPTI), we define the segment 22 to 27 as the binding loop of elafin, with the scissile peptide bond between Ala24 and Met25. In our solution structures, this loop is extended and solvent-exposed, and exhibits a large degree of flexibility. This mobility, already observed for the binding loop in other protease inhibitors in solution, might be an important feature for the interaction with the corresponding protease.

Selected figure(s)

Figure 4.
Figure 4. HSQC spectrum of r-elafin in 2 H2O at pH 7 and at 293 K showing most of the 13 C a resonances, all proline 13 C d resonances (Pd) and the three serine 13 C b resonances (Sb).

Figure 6.
Figure 6. A representation of the different inter-proton NOEs ( !) and the strong hydrogen bonds ( ) in the b-sheet.

The above figures are reprinted by permission from Elsevier: J Mol Biol (1997, 268, 666-677) copyright 1997.

Figures were selected by an automated process.