2h7f: Difference between revisions

[[Image:2h7f.gif|left|200px]]<br /><applet load="2h7f" size="350" color="white" frame="true" align="right" spinBox="true"  

Although smallpox has been eradicated from the human population, it is presently feared as a possible agent of bioterrorism. The smallpox virus codes for its own topoisomerase enzyme that differs from its cellular counterpart by requiring a specific DNA sequence for activation of catalysis. Here we present crystal structures of the smallpox virus topoisomerase enzyme bound both covalently and noncovalently to a specific DNA sequence. These structures reveal the basis for site-specific DNA recognition, and they explain how catalysis is likely activated by formation of a specific enzyme-DNA interface. Unexpectedly, the poxvirus enzyme uses a major groove binding alpha helix that is not present in the human enzyme to recognize part of the core recognition sequence and activate the enzyme for catalysis. The topoisomerase-DNA complex structures also provide a three-dimensional framework that may facilitate the rational design of therapeutic agents to treat poxvirus infections.

2H7F is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Variola_virus Variola virus]. Active as [http://en.wikipedia.org/wiki/DNA_topoisomerase DNA topoisomerase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=5.99.1.2 5.99.1.2] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2H7F OCA].  

[[Category: Bushman, F D.]]

[[Category: Duyne, G D.Van.]]

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