1kej
From Proteopedia
(New page: 200px<br /><applet load="1kej" size="450" color="white" frame="true" align="right" spinBox="true" caption="1kej, resolution 3.00Å" /> '''Crystal Structure of...) |
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| - | [[Image:1kej.jpg|left|200px]]<br /><applet load="1kej" size=" | + | [[Image:1kej.jpg|left|200px]]<br /><applet load="1kej" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1kej, resolution 3.00Å" /> | caption="1kej, resolution 3.00Å" /> | ||
'''Crystal Structure of Murine Terminal Deoxynucleotidyl Transferase complexed with ddATP'''<br /> | '''Crystal Structure of Murine Terminal Deoxynucleotidyl Transferase complexed with ddATP'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The crystal structure of the catalytic core of murine terminal | + | The crystal structure of the catalytic core of murine terminal deoxynucleotidyltransferase (TdT) at 2.35 A resolution reveals a typical DNA polymerase beta-like fold locked in a closed form. In addition, the structures of two different binary complexes, one with an oligonucleotide primer and the other with an incoming ddATP-Co(2+) complex, show that the substrates and the two divalent ions in the catalytic site are positioned in TdT in a manner similar to that described for the human DNA polymerase beta ternary complex, suggesting a common two metal ions mechanism of nucleotidyl transfer in these two proteins. The inability of TdT to accommodate a template strand can be explained by steric hindrance at the catalytic site caused by a long lariat-like loop, which is absent in DNA polymerase beta. However, displacement of this discriminating loop would be sufficient to unmask a number of evolutionarily conserved residues, which could then interact with a template DNA strand. The present structure can be used to model the recently discovered human polymerase mu, with which it shares 43% sequence identity. |
==About this Structure== | ==About this Structure== | ||
| - | 1KEJ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Mus_musculus Mus musculus] with CO, NA and DAD as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/DNA_nucleotidylexotransferase DNA nucleotidylexotransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.7.31 2.7.7.31] Full crystallographic information is available from [http:// | + | 1KEJ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Mus_musculus Mus musculus] with <scene name='pdbligand=CO:'>CO</scene>, <scene name='pdbligand=NA:'>NA</scene> and <scene name='pdbligand=DAD:'>DAD</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/DNA_nucleotidylexotransferase DNA nucleotidylexotransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.7.31 2.7.7.31] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1KEJ OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Mus musculus]] | [[Category: Mus musculus]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Boule, J | + | [[Category: Boule, J B.]] |
[[Category: Delarue, M.]] | [[Category: Delarue, M.]] | ||
[[Category: Expert-Bezancon, N.]] | [[Category: Expert-Bezancon, N.]] | ||
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[[Category: polymerase]] | [[Category: polymerase]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:33:13 2008'' |
Revision as of 11:33, 21 February 2008
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Crystal Structure of Murine Terminal Deoxynucleotidyl Transferase complexed with ddATP
Overview
The crystal structure of the catalytic core of murine terminal deoxynucleotidyltransferase (TdT) at 2.35 A resolution reveals a typical DNA polymerase beta-like fold locked in a closed form. In addition, the structures of two different binary complexes, one with an oligonucleotide primer and the other with an incoming ddATP-Co(2+) complex, show that the substrates and the two divalent ions in the catalytic site are positioned in TdT in a manner similar to that described for the human DNA polymerase beta ternary complex, suggesting a common two metal ions mechanism of nucleotidyl transfer in these two proteins. The inability of TdT to accommodate a template strand can be explained by steric hindrance at the catalytic site caused by a long lariat-like loop, which is absent in DNA polymerase beta. However, displacement of this discriminating loop would be sufficient to unmask a number of evolutionarily conserved residues, which could then interact with a template DNA strand. The present structure can be used to model the recently discovered human polymerase mu, with which it shares 43% sequence identity.
About this Structure
1KEJ is a Single protein structure of sequence from Mus musculus with , and as ligands. Active as DNA nucleotidylexotransferase, with EC number 2.7.7.31 Full crystallographic information is available from OCA.
Reference
Crystal structures of a template-independent DNA polymerase: murine terminal deoxynucleotidyltransferase., Delarue M, Boule JB, Lescar J, Expert-Bezancon N, Jourdan N, Sukumar N, Rougeon F, Papanicolaou C, EMBO J. 2002 Feb 1;21(3):427-39. PMID:11823435
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