Coupling between ATP Binding and DNA Cleavage by DNA Topoisomerase II
نویسندگان
چکیده
منابع مشابه
Coupling between ATP binding and DNA cleavage by DNA topoisomerase II: A unifying kinetic and structural mechanism.
DNA topoisomerase II is a molecular machine that couples ATP hydrolysis to the transport of one DNA segment through a transient break in another segment. To learn about the energetic connectivity that underlies this coupling, we investigated how the ATPase domains exert control over DNA cleavage. We dissected the DNA cleavage reaction by measuring rate and equilibrium constants for the individu...
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Topoisomerase II, purified from chicken erythrocytes, was reacted with a large number of different DNA fragments and cleavages were catalogued in the presence and absence of drugs that stabilize the cleavage intermediate. Cleavages were sequenced to derive a consensus for topoisomerase II that predicts catalytic sites. The consensus is: (sequence; see text) where N is any base and cleavage occu...
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DNA topoisomerase II is a homodimeric molecular machine that couples ATP usage to the transport of one DNA segment through a transient break in another segment. In the presence of a nonhydrolyzable ATP analog, the enzyme is known to promote a single turnover of DNA transport. Current models for the enzyme's mechanism based on this result have hydrolysis of two ATPs as the last step, used only t...
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ژورنال
عنوان ژورنال: Journal of Biological Chemistry
سال: 2008
ISSN: 0021-9258
DOI: 10.1074/jbc.m710014200