 |
PDBsum entry 1cp3
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Hydrolase/hydrolase inhibitor
|
PDB id
|
|
|
|
1cp3
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
 |
Contents |
 |
|
|
|
|
|
|
|
|
|
|
|
|
* Residue conservation analysis
|
|
|
|
|
References listed in PDB file
|
|
|
Key reference
|
|
|
Title
|
|
Structure of recombinant human cpp32 in complex with the tetrapeptide acetyl-Asp-Val-Ala-Asp fluoromethyl ketone.
|
|
|
Authors
|
|
P.R.Mittl,
S.Di marco,
J.F.Krebs,
X.Bai,
D.S.Karanewsky,
J.P.Priestle,
K.J.Tomaselli,
M.G.Grütter.
|
|
|
Ref.
|
|
J Biol Chem, 1997,
272,
6539-6547.
[DOI no: ]
|
|
|
PubMed id
|
|
|
|
|
|
Abstract
|
|
|
The cysteine protease CPP32 has been expressed in a soluble form in Escherichia
coli and purified to >95% purity. The three-dimensional structure of human CPP32
in complex with the irreversible tetrapeptide inhibitor acetyl-Asp-Val-Ala-Asp
fluoromethyl ketone was determined by x-ray crystallography at a resolution of
2.3 A. The asymmetric unit contains a (p17/p12)2 tetramer, in agreement with the
tetrameric structure of the protein in solution as determined by dynamic light
scattering and size exclusion chromatography. The overall topology of CPP32 is
very similar to that of interleukin-1beta-converting enzyme (ICE); however,
differences exist at the N terminus of the p17 subunit, where the first helix
found in ICE is missing in CPP32. A deletion/insertion pattern is responsible
for the striking differences observed in the loops around the active site. In
addition, the P1 carbonyl of the ketone inhibitor is pointing into the oxyanion
hole and forms a hydrogen bond with the peptidic nitrogen of Gly-122, resulting
in a different state compared with the tetrahedral intermediate observed in the
structure of ICE and CPP32 in complex with an aldehyde inhibitor. The topology
of the interface formed by the two p17/p12 heterodimers of CPP32 is different
from that of ICE. This results in different orientations of CPP32 heterodimers
compared with ICE heterodimers, which could affect substrate recognition. This
structural information will be invaluable for the design of small synthetic
inhibitors of CPP32 as well as for the design of CPP32 mutants.
|
|
|
|
|
|
|
|
Figure 7.
Fig. 7. Molecular surface of the CPP32 tetramer generated by
GRASP (45). The molecule is seen parallel to the 2-fold axis.
The surface is colored according to its electrostatic potential.
Red and blue areas represent negative and positive charge
density, respectively. Two Ac-DVAD-fmk molecules (colored
according to atom type) bind to the tetramer. The inhibitor
residues and the^ central cavity discussed under "Results and
Discussion" are labeled.
|
|
Figure 10.
Fig. 10. Schematic superposition of the ICE and CPP32
tetramers. The two CPP32 dimers are represented by dark and
light gray cylinders. The ICE tetramer is not shaded. Thick
arrows on the^ ends of the cylinders indicate the active sites.
When the superposition is made based on the residues from the
first p17/p12 dimers, the^ second dimers differ by a rigid-body
rotation of 13°. The rotation axis (dotted arrow) is
oriented perpendicular to the 2-fold axis.
|
|
|
|
|
|
The above figures are
reprinted
by permission from the ASBMB:
J Biol Chem
(1997,
272,
6539-6547)
copyright 1997.
|
|
|
|
|
|
|
