1bgx
From Proteopedia
(New page: 200px<br /> <applet load="1bgx" size="450" color="white" frame="true" align="right" spinBox="true" caption="1bgx, resolution 2.3Å" /> '''TAQ POLYMERASE IN CO...) |
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| - | [[Image:1bgx.gif|left|200px]]<br /> | + | [[Image:1bgx.gif|left|200px]]<br /><applet load="1bgx" size="350" color="white" frame="true" align="right" spinBox="true" |
| - | <applet load="1bgx" size=" | + | |
caption="1bgx, resolution 2.3Å" /> | caption="1bgx, resolution 2.3Å" /> | ||
'''TAQ POLYMERASE IN COMPLEX WITH TP7, AN INHIBITORY FAB'''<br /> | '''TAQ POLYMERASE IN COMPLEX WITH TP7, AN INHIBITORY FAB'''<br /> | ||
==Overview== | ==Overview== | ||
| - | We report the crystal structure of Thermus aquaticus DNA polymerase I in | + | We report the crystal structure of Thermus aquaticus DNA polymerase I in complex with an inhibitory Fab, TP7, directed against the native enzyme. Some of the residues present in a helical conformation in the native enzyme have adopted a gamma turn conformation in the complex. Taken together, structural information that describes alteration of helical structure and solution studies that demonstrate the ability of TP7 to inhibit 100% of the polymerase activity of the enzyme suggest that the change in conformation is probably caused by trapping of an intermediate in the helix-coil dynamics of this helix by the Fab. Antibodies directed against modified helices in proteins have long been anticipated. The present structure provides direct crystallographic evidence. The Fab binds within the DNA binding cleft of the polymerase domain, interacting with several residues that are used by the enzyme in binding the primer:template complex. This result unequivocally corroborates inferences drawn from binding experiments and modeling calculations that the inhibitory activity of this Fab is directly attributable to its interference with DNA binding by the polymerase domain of the enzyme. The combination of interactions made by the Fab residues in both the polymerase and the vestigial editing nuclease domain of the enzyme reveal the structural basis of its preference for binding to DNA polymerases of the Thermus species. The orientation of the structure-specific nuclease domain with respect to the polymerase domain is significantly different from that seen in other structures of this polymerase. This reorientation does not appear to be antibody-induced and implies remarkably high relative mobility between these two domains. |
==About this Structure== | ==About this Structure== | ||
| - | 1BGX is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Mus_musculus Mus musculus] and [http://en.wikipedia.org/wiki/Thermus_aquaticus Thermus aquaticus]. 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:// | + | 1BGX is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Mus_musculus Mus musculus] and [http://en.wikipedia.org/wiki/Thermus_aquaticus Thermus aquaticus]. 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=1BGX OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Protein complex]] | [[Category: Protein complex]] | ||
[[Category: Thermus aquaticus]] | [[Category: Thermus aquaticus]] | ||
| - | [[Category: Daiss, J | + | [[Category: Daiss, J L.]] |
[[Category: Murali, R.]] | [[Category: Murali, R.]] | ||
| - | [[Category: Murthy, H | + | [[Category: Murthy, H M.Krishna.]] |
| - | [[Category: Sharkey, D | + | [[Category: Sharkey, D J.]] |
[[Category: complex (polymerase/inhibitor)]] | [[Category: complex (polymerase/inhibitor)]] | ||
[[Category: dna polymerase]] | [[Category: dna polymerase]] | ||
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[[Category: pcr]] | [[Category: pcr]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 11:55:12 2008'' |
Revision as of 09:55, 21 February 2008
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TAQ POLYMERASE IN COMPLEX WITH TP7, AN INHIBITORY FAB
Overview
We report the crystal structure of Thermus aquaticus DNA polymerase I in complex with an inhibitory Fab, TP7, directed against the native enzyme. Some of the residues present in a helical conformation in the native enzyme have adopted a gamma turn conformation in the complex. Taken together, structural information that describes alteration of helical structure and solution studies that demonstrate the ability of TP7 to inhibit 100% of the polymerase activity of the enzyme suggest that the change in conformation is probably caused by trapping of an intermediate in the helix-coil dynamics of this helix by the Fab. Antibodies directed against modified helices in proteins have long been anticipated. The present structure provides direct crystallographic evidence. The Fab binds within the DNA binding cleft of the polymerase domain, interacting with several residues that are used by the enzyme in binding the primer:template complex. This result unequivocally corroborates inferences drawn from binding experiments and modeling calculations that the inhibitory activity of this Fab is directly attributable to its interference with DNA binding by the polymerase domain of the enzyme. The combination of interactions made by the Fab residues in both the polymerase and the vestigial editing nuclease domain of the enzyme reveal the structural basis of its preference for binding to DNA polymerases of the Thermus species. The orientation of the structure-specific nuclease domain with respect to the polymerase domain is significantly different from that seen in other structures of this polymerase. This reorientation does not appear to be antibody-induced and implies remarkably high relative mobility between these two domains.
About this Structure
1BGX is a Protein complex structure of sequences from Mus musculus and Thermus aquaticus. Active as DNA-directed DNA polymerase, with EC number 2.7.7.7 Full crystallographic information is available from OCA.
Reference
Crystal structure of Taq DNA polymerase in complex with an inhibitory Fab: the Fab is directed against an intermediate in the helix-coil dynamics of the enzyme., Murali R, Sharkey DJ, Daiss JL, Murthy HM, Proc Natl Acad Sci U S A. 1998 Oct 13;95(21):12562-7. PMID:9770525
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