1gpc
From Proteopedia
(New page: 200px<br /><applet load="1gpc" size="450" color="white" frame="true" align="right" spinBox="true" caption="1gpc, resolution 2.200Å" /> '''CORE GP32, DNA-BIND...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:1gpc.gif|left|200px]]<br /><applet load="1gpc" size=" | + | [[Image:1gpc.gif|left|200px]]<br /><applet load="1gpc" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1gpc, resolution 2.200Å" /> | caption="1gpc, resolution 2.200Å" /> | ||
'''CORE GP32, DNA-BINDING PROTEIN'''<br /> | '''CORE GP32, DNA-BINDING PROTEIN'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The single-stranded DNA (ssDNA) binding protein gp32 from bacteriophage T4 | + | The single-stranded DNA (ssDNA) binding protein gp32 from bacteriophage T4 is essential for T4 DNA replication, recombination and repair. In vivo gp32 binds ssDNA as the replication fork advances and stimulates replisome processivity and accuracy by a factor of several hundred. Gp32 binding affects nearly every major aspect of DNA metabolism. Among its important functions are: (1) configuring ssDNA templates for efficient use by the replisome including DNA polymerase; (2) melting out adventitious secondary structures; (3) protecting exposed ssDNA from nucleases; and (4) facilitating homologous recombination by binding ssDNA during strand displacement. We have determined the crystal structure of the gp32 DNA binding domain complexed to ssDNA at 2.2 A resolution. The ssDNA binding cleft comprises regions from three structural subdomains and includes a positively charged surface that runs parallel to a series of hydrophobic pockets formed by clusters of aromatic side chains. Although only weak electron density is seen for the ssDNA, it indicates that the phosphate backbone contacts an electropositive cleft of the protein, placing the bases in contact with the hydrophobic pockets. The DNA mobility implied by the weak electron density may reflect the role of gp32 as a sequence-independent ssDNA chaperone allowing the largely unstructured ssDNA to slide freely through the cleft. |
==About this Structure== | ==About this Structure== | ||
| - | 1GPC is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacteriophage_t4 Bacteriophage t4] with ZN as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | + | 1GPC is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacteriophage_t4 Bacteriophage t4] with <scene name='pdbligand=ZN:'>ZN</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GPC OCA]. |
==Reference== | ==Reference== | ||
| Line 13: | Line 13: | ||
[[Category: Bacteriophage t4]] | [[Category: Bacteriophage t4]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Friedman, A | + | [[Category: Friedman, A M.]] |
| - | [[Category: Konigsberg, W | + | [[Category: Konigsberg, W H.]] |
| - | [[Category: Parsons, M | + | [[Category: Parsons, M R.]] |
[[Category: Shamoo, Y.]] | [[Category: Shamoo, Y.]] | ||
| - | [[Category: Steitz, T | + | [[Category: Steitz, T A.]] |
[[Category: ZN]] | [[Category: ZN]] | ||
[[Category: single-stranded dna-binding]] | [[Category: single-stranded dna-binding]] | ||
| Line 23: | Line 23: | ||
[[Category: zinc binding domain]] | [[Category: zinc binding domain]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:52:32 2008'' |
Revision as of 10:52, 21 February 2008
|
CORE GP32, DNA-BINDING PROTEIN
Overview
The single-stranded DNA (ssDNA) binding protein gp32 from bacteriophage T4 is essential for T4 DNA replication, recombination and repair. In vivo gp32 binds ssDNA as the replication fork advances and stimulates replisome processivity and accuracy by a factor of several hundred. Gp32 binding affects nearly every major aspect of DNA metabolism. Among its important functions are: (1) configuring ssDNA templates for efficient use by the replisome including DNA polymerase; (2) melting out adventitious secondary structures; (3) protecting exposed ssDNA from nucleases; and (4) facilitating homologous recombination by binding ssDNA during strand displacement. We have determined the crystal structure of the gp32 DNA binding domain complexed to ssDNA at 2.2 A resolution. The ssDNA binding cleft comprises regions from three structural subdomains and includes a positively charged surface that runs parallel to a series of hydrophobic pockets formed by clusters of aromatic side chains. Although only weak electron density is seen for the ssDNA, it indicates that the phosphate backbone contacts an electropositive cleft of the protein, placing the bases in contact with the hydrophobic pockets. The DNA mobility implied by the weak electron density may reflect the role of gp32 as a sequence-independent ssDNA chaperone allowing the largely unstructured ssDNA to slide freely through the cleft.
About this Structure
1GPC is a Single protein structure of sequence from Bacteriophage t4 with as ligand. Full crystallographic information is available from OCA.
Reference
Crystal structure of a replication fork single-stranded DNA binding protein (T4 gp32) complexed to DNA., Shamoo Y, Friedman AM, Parsons MR, Konigsberg WH, Steitz TA, Nature. 1995 Jul 27;376(6538):362-6. PMID:7630406
Page seeded by OCA on Thu Feb 21 12:52:32 2008
