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PDBsum entry 1nns
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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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Structural comparison of escherichia coli l-Asparaginase in two monoclinic space groups.
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Authors
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M.Sanches,
J.A.Barbosa,
R.T.De oliveira,
J.Abrahão neto,
I.Polikarpov.
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Ref.
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Acta Crystallogr D Biol Crystallogr, 2003,
59,
416-422.
[DOI no: ]
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PubMed id
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Abstract
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The functional L-asparaginase from Escherichia coli is a homotetramer with a
molecular weight of about 142 kDa. The X-ray structure of the enzyme,
crystallized in a new form (space group C2) and refined to 1.95 A resolution, is
compared with that of the previously determined crystal form (space group
P2(1)). The asymmetric unit of the new crystal form contains an L-asparaginase
dimer instead of the tetramer found in the previous crystal form. It is found
that crystal contacts practically do not affect the conformation of the protein.
It is shown that subunit C of the tetrameric form is in a conformation which is
systematically different from that of all other subunits in both crystal forms.
Major conformational differences are confined to the lid loop (residues 14-27).
In addition, the stability of this globular protein is analyzed in terms of the
interactions between hydrophobic parts of the subunits.
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Figure 2.
Figure 2 A schematic representation of the E. coli
L-asparaginase subunit produced using MOLSCRIPT (Kraulis,
1991[Kraulis, P. J. (1991). J. Appl. Cryst. 24, 946-950.]).
Secondary structures marked N belong to the N-terminal domain
and those marked C belong to the C-terminal domain. The
3[10]-helices N  1,
N 3,
N 6
and N 10
are shown in opaque green.
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Figure 3.
Figure 3 A graphical representation of the L-asparaginase
tetramer produced using MOLSCRIPT (Kraulis, 1991[Kraulis, P. J.
(1991). J. Appl. Cryst. 24, 946-950.]). Intimate dimers are
formed by subunits drawn in yellow/blue and green/pink.
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The above figures are
reprinted
by permission from the IUCr:
Acta Crystallogr D Biol Crystallogr
(2003,
59,
416-422)
copyright 2003.
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Secondary reference #1
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Title
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Preparation and preliminary X-Ray diffraction studies of a new crystal form of l-Asparaginase from escherichia coli.
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Authors
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I.Polikarpov,
R.T.De oliveira,
J.Abrahão-Neto.
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Ref.
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Acta Crystallogr D Biol Crystallogr, 1999,
55,
1616-1617.
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PubMed id
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Secondary reference #2
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Title
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Crystal structure of escherichia coli l-Asparaginase, An enzyme used in cancer therapy.
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Authors
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A.L.Swain,
M.Jaskólski,
D.Housset,
J.K.Rao,
A.Wlodawer.
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Ref.
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Proc Natl Acad Sci U S A, 1993,
90,
1474-1478.
[DOI no: ]
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PubMed id
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