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PDBsum entry 1fn6
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Contents |
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* Residue conservation analysis
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References listed in PDB file
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Key reference
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Title
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Structures of porcine beta-Trypsin-Detergent complexes: the stabilization of proteins through hydrophilic binding of polydocanol.
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Authors
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S.Deepthi,
A.Johnson,
V.Pattabhi.
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Ref.
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Acta Crystallogr D Biol Crystallogr, 2001,
57,
1506-1512.
[DOI no: ]
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PubMed id
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Abstract
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Polydocanol has a wide range of medical applications, especially in
sclerotherapy of many diseases such as gastrointestinal antiplastia, oesophageal
haemangioma etc. It is of interest to study the mode of binding of this
medically important detergent and its subsequent action on proteins. Here, three
crystal structures of serine protease trypsin are reported in the presence of
varying concentrations of polydocanol in order to elucidate its mode of binding
and interactions with proteins. Polydocanol binds to the protein with its
hydrophilic head rather than the hydrophobic tail as is the case with other
detergents such as SDS and MEGA-8. This hydrophilic binding mode results in the
binding sites of polydocanol being distributed on the surface of the enzyme.
There are at least 11 binding sites for polydocanol in trypsin. Polydocanol
forms part of the large-scale water networks which connect distant regions of
the enzyme, thereby stabilizing it. The hydrophilic binding of polydocanol also
results in cross-linked pairs of trypsin molecules.
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Figure 1.
Figure 1 2F[o] - F[c] (darker lines) with 1  and
F[o] - F[c] (lighter lines) with 2 level
omit maps (residues 29-56 are omitted) showing GYC density and
GYC-mediated intermolecular interactions of the protein.
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Figure 4.
Figure 4 2F[o] - F[c] map showing electron density for a sulfate
molecule at the active site. Hydrogen bonds with His57, Ser195
and Gly193 are also shown.
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The above figures are
reprinted
by permission from the IUCr:
Acta Crystallogr D Biol Crystallogr
(2001,
57,
1506-1512)
copyright 2001.
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Secondary reference #1
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Title
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Crystal structure at 1.63 a resolution of the native form of porcine beta-Trypsin: revealing an acetate ion binding site and functional water network.
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Authors
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A.Johnson,
N.Gautham,
V.Pattabhi.
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Ref.
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Biochim Biophys Acta, 1999,
1435,
7.
[DOI no: ]
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PubMed id
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Secondary reference #2
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Title
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The first structure at 1.8 a resolution of an active autolysate form of porcine alpha-Trysoin.
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Authors
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A.Johnson,
S.Krishnaswamy,
P.V.Sundaram,
V.Pattabhi.
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Ref.
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Acta Crystallogr D Biol Crystallogr, 1997,
53,
311-315.
[DOI no: ]
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PubMed id
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Figure 2.
Fig. 2. Stereoview of the
2Fo-Fc map around the
autolysis site Lys145-Ser146
of APT.
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Figure 5.
Fig. 5. Superposition of the C
~
traces of APT (yellow line), EPT
(green line) and MCT (red line).
Active-site residues are shown in
ball-and-stick representation. See
text for details.
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The above figures are
reproduced from the cited reference
with permission from the IUCr
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