1lv5
From Proteopedia
| Line 1: | Line 1: | ||
[[Image:1lv5.jpg|left|200px]] | [[Image:1lv5.jpg|left|200px]] | ||
| - | + | <!-- | |
| - | + | The line below this paragraph, containing "STRUCTURE_1lv5", creates the "Structure Box" on the page. | |
| - | + | You may change the PDB parameter (which sets the PDB file loaded into the applet) | |
| - | + | or the SCENE parameter (which sets the initial scene displayed when the page is loaded), | |
| - | + | or leave the SCENE parameter empty for the default display. | |
| - | | | + | --> |
| - | | | + | {{STRUCTURE_1lv5| PDB=1lv5 | SCENE= }} |
| - | + | ||
| - | + | ||
| - | }} | + | |
'''Crystal Structure of the Closed Conformation of Bacillus DNA Polymerase I Fragment Bound to DNA and dCTP''' | '''Crystal Structure of the Closed Conformation of Bacillus DNA Polymerase I Fragment Bound to DNA and dCTP''' | ||
| Line 29: | Line 26: | ||
[[Category: Johnson, S J.]] | [[Category: Johnson, S J.]] | ||
[[Category: Taylor, J S.]] | [[Category: Taylor, J S.]] | ||
| - | [[Category: | + | [[Category: Closed conformation]] |
| - | [[Category: | + | [[Category: Dna polymerase i]] |
| - | [[Category: | + | [[Category: Dna replication]] |
| - | [[Category: | + | [[Category: Klenow fragment]] |
| - | [[Category: | + | [[Category: Protein-dna-dntp complex]] |
| - | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 00:19:30 2008'' | |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | |
Revision as of 21:19, 2 May 2008
Crystal Structure of the Closed Conformation of Bacillus DNA Polymerase I Fragment Bound to DNA and dCTP
Overview
DNA polymerases replicate DNA by adding nucleotides to a growing primer strand while avoiding frameshift and point mutations. Here we present a series of up to six successive replication events that were obtained by extension of a primed template directly in a crystal of the thermostable Bacillus DNA polymerase I. The 6-bp extension involves a 20-A translocation of the DNA duplex, representing the largest molecular movement observed in a protein crystal. In addition, we obtained the structure of a "closed" conformation of the enzyme with a bound triphosphate juxtaposed to a template and a dideoxy-terminated primer by constructing a point mutant that destroys a crystal lattice contact stabilizing the wild-type polymerase in an "open" conformation. Together, these observations allow many of the steps involved in DNA replication to be observed in the same enzyme at near atomic detail. The successive replication events observed directly by catalysis in the crystal confirm the general reaction sequence deduced from observations obtained by using several other polymerases and further refine critical aspects of the known reaction mechanism, and also allow us to propose new features that concern the regulated transfer of the template strand between a preinsertion site and an insertion site. We propose that such regulated transfer is an important element in the prevention of frameshift mutations in high-fidelity DNA polymerases. The ability to observe processive, high-fidelity replication directly in a crystal establishes this polymerase as a powerful model system for mechanistic studies in which the structural consequences of mismatches and DNA adducts are observed.
About this Structure
1LV5 is a Single protein structure of sequence from Geobacillus stearothermophilus. Full crystallographic information is available from OCA.
Reference
Processive DNA synthesis observed in a polymerase crystal suggests a mechanism for the prevention of frameshift mutations., Johnson SJ, Taylor JS, Beese LS, Proc Natl Acad Sci U S A. 2003 Apr 1;100(7):3895-900. Epub 2003 Mar 20. PMID:12649320 Page seeded by OCA on Sat May 3 00:19:30 2008
