2ago: Difference between revisions

From Proteopedia
Jump to navigation Jump to search
No edit summary
No edit summary
Line 1: Line 1:
[[Image:2ago.gif|left|200px]]
{{Seed}}
[[Image:2ago.png|left|200px]]


<!--
<!--
Line 9: Line 10:
{{STRUCTURE_2ago|  PDB=2ago  |  SCENE=  }}  
{{STRUCTURE_2ago|  PDB=2ago  |  SCENE=  }}  


'''Fidelity of Dpo4: effect of metal ions, nucleotide selection and pyrophosphorolysis'''
===Fidelity of Dpo4: effect of metal ions, nucleotide selection and pyrophosphorolysis===




==Overview==
<!--
We report the crystal structures of a translesion DNA polymerase, Dpo4, complexed with a matched or mismatched incoming nucleotide and with a pyrophosphate product after misincorporation. These structures suggest two mechanisms by which Dpo4 may reject a wrong incoming nucleotide with its preformed and open active site. First, a mismatched replicating base pair leads to poor base stacking and alignment of the metal ions and as a consequence, inhibits incorporation. By replacing Mg2+ with Mn2+, which has a relaxed coordination requirement and tolerates misalignment, the catalytic efficiency of misincorporation increases dramatically. Mn2+ also enhances translesion synthesis by Dpo4. Subtle conformational changes that lead to the proper metal ion coordination may, therefore, be a key step in catalysis. Second, the slow release of pyrophosphate may increase the fidelity of Dpo4 by stalling mispaired primer extension and promoting pyrophosphorolysis that reverses the polymerization reaction. Indeed, Dpo4 has robust pyrophosphorolysis activity and degrades the primer strand in the presence of pyrophosphate. The correct incoming nucleotide allows DNA synthesis to overcome pyrophosphorolysis, but an incorrect incoming nucleotide does not.
The line below this paragraph, {{ABSTRACT_PUBMED_16107880}}, adds the Publication Abstract to the page
(as it appears on PubMed at http://www.pubmed.gov), where 16107880 is the PubMed ID number.
-->
{{ABSTRACT_PUBMED_16107880}}


==About this Structure==
==About this Structure==
Line 30: Line 34:
[[Category: Mismatch]]
[[Category: Mismatch]]
[[Category: Pyrophosphorolysis]]
[[Category: Pyrophosphorolysis]]
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May  3 19:01:38 2008''
 
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Tue Jul 29 01:57:06 2008''

Revision as of 01:57, 29 July 2008

File:2ago.png

Template:STRUCTURE 2ago

Fidelity of Dpo4: effect of metal ions, nucleotide selection and pyrophosphorolysisFidelity of Dpo4: effect of metal ions, nucleotide selection and pyrophosphorolysis

Template:ABSTRACT PUBMED 16107880

About this StructureAbout this Structure

2AGO is a Single protein structure of sequence from Sulfolobus solfataricus. Full crystallographic information is available from OCA.

ReferenceReference

Fidelity of Dpo4: effect of metal ions, nucleotide selection and pyrophosphorolysis., Vaisman A, Ling H, Woodgate R, Yang W, EMBO J. 2005 Sep 7;24(17):2957-67. Epub 2005 Aug 18. PMID:16107880

Page seeded by OCA on Tue Jul 29 01:57:06 2008

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA