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Structural similarities between topoisomerases that cleave one or both DNA strands.

ABSTRACT: Type IA and type II DNA topoisomerases are distinguished by their ability to cleave one or two strands, respectively, of a DNA duplex. Both types have been proposed to use an "enzyme-bridging" mechanism, in which a break is formed in a DNA strand and a gap is opened between the broken pieces to allow passage of a second DNA strand or duplex segment. Although the type IA and type II topoisomerase structures appear overall quite different from one another, unexpected similarities between several structural elements suggest that members of the two subfamilies may use comparable mechanisms to bind and cleave DNA.

SUBMITTER: Berger JM

PROVIDER: S-EPMC20897 | biostudies-literature | 1998 Jul

REPOSITORIES: biostudies-literature

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Structural similarities between topoisomerases that cleave one or both DNA strands.

Berger J M JM Fass D D Wang J C JC Harrison S C SC

Proceedings of the National Academy of Sciences of the United States of America 19980701 14

Type IA and type II DNA topoisomerases are distinguished by their ability to cleave one or two strands, respectively, of a DNA duplex. Both types have been proposed to use an "enzyme-bridging" mechanism, in which a break is formed in a DNA strand and a gap is opened between the broken pieces to allow passage of a second DNA strand or duplex segment. Although the type IA and type II topoisomerase structures appear overall quite different from one another, unexpected similarities between several s ...[more]

PMID: 9653108

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