1s76
From Proteopedia
(New page: 200px<br /><applet load="1s76" size="450" color="white" frame="true" align="right" spinBox="true" caption="1s76, resolution 2.88Å" /> '''T7 RNA polymerase al...) |
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| - | [[Image:1s76.gif|left|200px]]<br /><applet load="1s76" size=" | + | [[Image:1s76.gif|left|200px]]<br /><applet load="1s76" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1s76, resolution 2.88Å" /> | caption="1s76, resolution 2.88Å" /> | ||
'''T7 RNA polymerase alpha beta methylene ATP elongation complex'''<br /> | '''T7 RNA polymerase alpha beta methylene ATP elongation complex'''<br /> | ||
==Overview== | ==Overview== | ||
| - | RNA polymerase functions like a molecular motor that can convert chemical | + | RNA polymerase functions like a molecular motor that can convert chemical energy into the work of strand separation and translocation along the DNA during transcription. The structures of phage T7 RNA polymerase in an elongation phase substrate complex that includes the incoming nucleoside triphosphate and a pretranslocation product complex that includes the product pyrophosphate (PPi) are described here. These structures and the previously determined posttranslocation elongation complex demonstrate that two enzyme conformations exist during a cycle of single nucleotide addition. One orientation of a five-helix subdomain is stabilized by the phosphates of either the incoming NTP or by the product PPi. A second orientation of this subdomain is stable in their absence and is associated with translocation of the heteroduplex product as well as strand separation of the downstream DNA. We propose that the dissociation of the product PPi after nucleotide addition produces the protein conformational change resulting in translocation and strand separation. |
==About this Structure== | ==About this Structure== | ||
| - | 1S76 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacteriophage_t7 Bacteriophage t7] with MG and APC as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/DNA-directed_RNA_polymerase DNA-directed RNA polymerase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.7.6 2.7.7.6] Full crystallographic information is available from [http:// | + | 1S76 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacteriophage_t7 Bacteriophage t7] with <scene name='pdbligand=MG:'>MG</scene> and <scene name='pdbligand=APC:'>APC</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/DNA-directed_RNA_polymerase DNA-directed RNA polymerase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.7.6 2.7.7.6] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1S76 OCA]. |
==Reference== | ==Reference== | ||
| Line 14: | Line 14: | ||
[[Category: DNA-directed RNA polymerase]] | [[Category: DNA-directed RNA polymerase]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Steitz, T | + | [[Category: Steitz, T A.]] |
| - | [[Category: Yin, Y | + | [[Category: Yin, Y W.]] |
[[Category: APC]] | [[Category: APC]] | ||
[[Category: MG]] | [[Category: MG]] | ||
[[Category: t7 rna polymerase]] | [[Category: t7 rna polymerase]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:58:41 2008'' |
Revision as of 12:58, 21 February 2008
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T7 RNA polymerase alpha beta methylene ATP elongation complex
Overview
RNA polymerase functions like a molecular motor that can convert chemical energy into the work of strand separation and translocation along the DNA during transcription. The structures of phage T7 RNA polymerase in an elongation phase substrate complex that includes the incoming nucleoside triphosphate and a pretranslocation product complex that includes the product pyrophosphate (PPi) are described here. These structures and the previously determined posttranslocation elongation complex demonstrate that two enzyme conformations exist during a cycle of single nucleotide addition. One orientation of a five-helix subdomain is stabilized by the phosphates of either the incoming NTP or by the product PPi. A second orientation of this subdomain is stable in their absence and is associated with translocation of the heteroduplex product as well as strand separation of the downstream DNA. We propose that the dissociation of the product PPi after nucleotide addition produces the protein conformational change resulting in translocation and strand separation.
About this Structure
1S76 is a Single protein structure of sequence from Bacteriophage t7 with and as ligands. Active as DNA-directed RNA polymerase, with EC number 2.7.7.6 Full crystallographic information is available from OCA.
Reference
The structural mechanism of translocation and helicase activity in T7 RNA polymerase., Yin YW, Steitz TA, Cell. 2004 Feb 6;116(3):393-404. PMID:15016374
Page seeded by OCA on Thu Feb 21 14:58:41 2008
