1d9d
From Proteopedia
(New page: 200px<br /><applet load="1d9d" size="450" color="white" frame="true" align="right" spinBox="true" caption="1d9d, resolution 2.18Å" /> '''CRYSTALL STRUCTURE O...) |
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| - | [[Image:1d9d.gif|left|200px]]<br /><applet load="1d9d" size=" | + | [[Image:1d9d.gif|left|200px]]<br /><applet load="1d9d" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1d9d, resolution 2.18Å" /> | caption="1d9d, resolution 2.18Å" /> | ||
'''CRYSTALL STRUCTURE OF THE COMPLEX OF DNA POLYMERASE I KLENOW FRAGMENT WITH SHORT DNA FRAGMENT CARRYING 2'-0-AMINOPROPYL-RNA MODIFICATIONS 5'-D(TCG)-AP(AUC)-3''''<br /> | '''CRYSTALL STRUCTURE OF THE COMPLEX OF DNA POLYMERASE I KLENOW FRAGMENT WITH SHORT DNA FRAGMENT CARRYING 2'-0-AMINOPROPYL-RNA MODIFICATIONS 5'-D(TCG)-AP(AUC)-3''''<br /> | ||
==Overview== | ==Overview== | ||
| - | Nuclease resistance and RNA affinity are key criteria in the search for | + | Nuclease resistance and RNA affinity are key criteria in the search for optimal antisense nucleic acid modifications, but the origins of the various levels of resistance to nuclease degradation conferred by chemical modification of DNA and RNA are currently not understood. The 2'-O-aminopropyl (AP)-RNA modification displays the highest nuclease resistance among all phosphodiester-based analogues and its RNA binding affinity surpasses that of phosphorothioate DNA by 1 degrees C per modified residue. We found that oligodeoxynucleotides containing AP-RNA residues at their 3' ends competitively inhibit the degradation of single-stranded DNA by the Escherichia coli Klenow fragment (KF) 3'-5' exonuclease and snake venom phosphodiesterase. To shed light on the origins of nuclease resistance brought about by the AP modification, we determined the crystal structure of an A-form DNA duplex with AP-RNA modifications at 1.6-A resolution. In addition, the crystal structures of complexes between short DNA fragments carrying AP-RNA modifications and wild-type KF were determined at resolutions between 2.2 and 3.0 A and compared with the structure of the complex between oligo(dT) and the D355A/E357A KF mutant. The structural models suggest that interference of the positively charged 2'-O-substituent with the metal ion binding site B of the exonuclease allows AP-RNA to effectively slow down degradation. |
==About this Structure== | ==About this Structure== | ||
| - | 1D9D is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with ZN, MG and SO4 as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/DNA-directed_DNA_polymerase DNA-directed DNA polymerase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.7.7 2.7.7.7] Full crystallographic information is available from [http:// | + | 1D9D is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with <scene name='pdbligand=ZN:'>ZN</scene>, <scene name='pdbligand=MG:'>MG</scene> and <scene name='pdbligand=SO4:'>SO4</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/DNA-directed_DNA_polymerase DNA-directed DNA polymerase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.7.7 2.7.7.7] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1D9D OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Cook, P | + | [[Category: Cook, P D.]] |
[[Category: Egli, M.]] | [[Category: Egli, M.]] | ||
[[Category: Manoharan, M.]] | [[Category: Manoharan, M.]] | ||
[[Category: Minasov, G.]] | [[Category: Minasov, G.]] | ||
| - | [[Category: Simons, A | + | [[Category: Simons, A M.]] |
[[Category: Teplova, M.]] | [[Category: Teplova, M.]] | ||
[[Category: Tereshko, V.]] | [[Category: Tereshko, V.]] | ||
| - | [[Category: Wallace, S | + | [[Category: Wallace, S T.]] |
[[Category: MG]] | [[Category: MG]] | ||
[[Category: SO4]] | [[Category: SO4]] | ||
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[[Category: klenow fragment]] | [[Category: klenow fragment]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:14:25 2008'' |
Revision as of 10:14, 21 February 2008
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CRYSTALL STRUCTURE OF THE COMPLEX OF DNA POLYMERASE I KLENOW FRAGMENT WITH SHORT DNA FRAGMENT CARRYING 2'-0-AMINOPROPYL-RNA MODIFICATIONS 5'-D(TCG)-AP(AUC)-3'
Overview
Nuclease resistance and RNA affinity are key criteria in the search for optimal antisense nucleic acid modifications, but the origins of the various levels of resistance to nuclease degradation conferred by chemical modification of DNA and RNA are currently not understood. The 2'-O-aminopropyl (AP)-RNA modification displays the highest nuclease resistance among all phosphodiester-based analogues and its RNA binding affinity surpasses that of phosphorothioate DNA by 1 degrees C per modified residue. We found that oligodeoxynucleotides containing AP-RNA residues at their 3' ends competitively inhibit the degradation of single-stranded DNA by the Escherichia coli Klenow fragment (KF) 3'-5' exonuclease and snake venom phosphodiesterase. To shed light on the origins of nuclease resistance brought about by the AP modification, we determined the crystal structure of an A-form DNA duplex with AP-RNA modifications at 1.6-A resolution. In addition, the crystal structures of complexes between short DNA fragments carrying AP-RNA modifications and wild-type KF were determined at resolutions between 2.2 and 3.0 A and compared with the structure of the complex between oligo(dT) and the D355A/E357A KF mutant. The structural models suggest that interference of the positively charged 2'-O-substituent with the metal ion binding site B of the exonuclease allows AP-RNA to effectively slow down degradation.
About this Structure
1D9D is a Single protein structure of sequence from Escherichia coli with , and as ligands. Active as DNA-directed DNA polymerase, with EC number 2.7.7.7 Full crystallographic information is available from OCA.
Reference
Structural origins of the exonuclease resistance of a zwitterionic RNA., Teplova M, Wallace ST, Tereshko V, Minasov G, Symons AM, Cook PD, Manoharan M, Egli M, Proc Natl Acad Sci U S A. 1999 Dec 7;96(25):14240-5. PMID:10588690
Page seeded by OCA on Thu Feb 21 12:14:25 2008
