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PDBsum entry 1ssc
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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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1.6 a structure of semisynthetic ribonuclease crystallized from aqueous ethanol. Comparison with crystals from salt solutions and with ribonuclease a from aqueous alcohol solutions.
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Authors
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S.J.De mel,
M.S.Doscher,
P.D.Martin,
F.Rodier,
B.F.Edwards.
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Ref.
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Acta Crystallogr D Biol Crystallogr, 1995,
51,
1003-1012.
[DOI no: ]
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PubMed id
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Note In the PDB file this reference is
annotated as "TO BE PUBLISHED".
The citation details given above were identified by an automated
search of PubMed on title and author
names, giving a
percentage match of
88%.
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Abstract
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The non-covalent combination of residues 1-118 of RNase A with a synthetic
14-residue peptide containing residues 111-124 of the molecule forms a highly
active semisynthetic enzyme, RNase 1-118:111-124. With this enzyme, the roles
played by the six C-terminal residues in generating the catalytic efficiency and
substrate specificity of RNase can be studied using chemically synthesized
analogs. The structure of RNase 1-118:111-124 from 43% aqueous ethanol has been
determined using molecular-replacement methods and refined to a crystallographic
R-factor of 0.166 for all observed reflections in the range 7.0-1.6 A (Protein
Data Bank file ISSC). The structure is compared with the 2.0 A structure of
RNase A from 43% aqueous 2-methyl-2-propanol and with the 1.8 A structure of the
semisynthetic enzyme obtained from crystals grown in concentrated salt solution.
The structure of RNase 1-118:111-124 from aqueous ethanol is virtually identical
to that of RNase A from aqueous 2-methyl-2-propanol. Half of the
crystallographically bound water molecules are not coincident, however. The
structure is somewhat less similar to that of RNase 1-118:111-124 from salt
solutions, with a major difference being the positioning of active-site residue
His119.
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Figure 4.
Fig. 4. Electron density for Hisil9 in RNase 1-118:111-124 from
aqueous ethanol. The
2F,,- F,.
density peaks for the imidazole ring
of Hisll9 and for the phosphate ion in RNase i-118:111-124
crystallized from aqueous ethanol contoured at 1.5cr. The side chain
is in position A.
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The above figure is
reprinted
by permission from the IUCr:
Acta Crystallogr D Biol Crystallogr
(1995,
51,
1003-1012)
copyright 1995.
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Secondary reference #1
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Title
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Structural changes that accompany the reduced catalytic efficiency of two semisynthetic ribonuclease analogs.
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Authors
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V.S.Demel,
P.D.Martin,
M.S.Doscher,
B.F.Edwards.
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Ref.
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J Biol Chem, 1992,
267,
247-256.
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PubMed id
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Secondary reference #2
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Title
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The refined crystal structure of a fully active semisynthetic ribonuclease at 1.8-A resolution.
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Authors
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P.D.Martin,
M.S.Doscher,
B.F.Edwards.
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Ref.
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J Biol Chem, 1987,
262,
15930-15938.
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PubMed id
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