 |
PDBsum entry 1dyt
|
|
|
|
|
 |
Contents |
 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
* Residue conservation analysis
|
|
|
|
|
References listed in PDB file
|
|
|
Key reference
|
|
|
Title
|
|
Three-Dimensional crystal structure of human eosinophil cationic protein (rnase 3) at 1.75 a resolution.
|
|
|
Authors
|
|
G.Mallorquí-Fernández,
J.Pous,
R.Peracaula,
J.Aymamí,
T.Maeda,
H.Tada,
H.Yamada,
M.Seno,
R.De llorens,
F.X.Gomis-Rüth,
M.Coll.
|
|
|
Ref.
|
|
J Mol Biol, 2000,
300,
1297-1307.
[DOI no: ]
|
|
|
PubMed id
|
|
|
|
|
|
Abstract
|
|
|
Eosinophil cationic protein (ECP; RNase 3) is a human ribonuclease found only in
eosinophil leukocytes that belongs to the RNase A superfamily. This enzyme is
bactericidal, helminthotoxic and cytotoxic to mammalian cells and tissues. The
protein has been cloned, heterologously overexpressed, purified and
crystallized. Its crystal structure has been determined and refined using data
up to 1. 75 A resolution. The molecule displays the alpha+beta folding topology
typical for members of the ribonuclease A superfamily. The catalytic active site
residues are conserved with respect to other ribonucleases of the superfamily
but some differences appear at substrate recognition subsites, which may
account, in part, for the low catalytic activity. Most strikingly, 19
surface-located arginine residues confer a strong basic character to the
protein. The high concentration of positive charges and the particular
orientation of the side-chains of these residues may also be related to the low
activity of ECP as a ribonuclease and provides an explanation for its unique
cytotoxic role through cell membrane disruption.
|
|
|
|
|
|
|
|
Figure 2.
Figure 2. Ribbon representation of the ECP polypep-
tide fold. The labelled helices (a1-a3), strands (b1-b6)
and loops are shown as helical ribbons, arrows and thin
tubes, respectively. Labelling is according to Figure 1.
|
|
Figure 3.
Figure 3. View of the Connolly surfaces displaying
the electrostatic potential (ranging from
-15
kBT/e (red)
to
+15
kBT/e (blue)) of ECP (top), view into (a) and
along (b) the active site cleft, and RNase A (bottom),
view into (c) and along (d) the active site cleft.
|
|
|
|
|
|
The above figures are
reprinted
by permission from Elsevier:
J Mol Biol
(2000,
300,
1297-1307)
copyright 2000.
|
|
|
|
|
|
|
