Structure of Ecballium elaterium trypsin inhibitor II (EETI-II): a rigid molecular scaffold.
The Ecballium elaterium trypsin inhibitor II (EETI-II) belongs to the family of squash inhibitors and is one of the strongest inhibitors known for trypsin. The eight independent molecules of EETI-II in the crystal structure reported here provide a good opportunity to test the hypothesis that this small cystine-knot protein (knottin) is sufficiently rigid to be used as a molecular scaffold for protein-engineering purposes. To extend this test, the structures of two complexes of EETI-II with trypsin have also been determined, one carrying a four-amino-acid mutation of EETI-II. The remarkable similarity of these structures confirms the rigidity of the molecular framework and hence its suitability as a molecular scaffold.
Krätzner
Ralph
R
Lehrstuhl für Strukturchemie, Georg-August-Universität Göttingen, Tammannstrasse 4, D37077 Göttingen, Germany.
Debreczeni
Judit E
JE
Pape
Thomas
T
Schneider
Thomas R
TR
Wentzel
Alexander
A
Kolmar
Harald
H
Sheldrick
George M
GM
Uson
Isabel
I
D018360:Crystallography, X-Ray; D015394:Molecular Structure; D009154:Mutation; D010940:Plant Proteins / Q000737:chemistry* / Q000235:genetics; D011485:Protein Binding; D015202:Protein Engineering / Q000379:methods; D014361:Trypsin Inhibitors / Q000737:chemistry
D010940:Plant Proteins; D014361:Trypsin Inhibitors; C063950:trypsin inhibitor EETI II protein, plant