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Insight into the cooperative DNA binding of the O?-alkylguanine DNA alkyltransferase.

ABSTRACT: The O(6)-alkylguanine DNA alkyltransferase (AGT) is a highly conserved protein responsible for direct repair of alkylated guanine and to a lesser degree thymine bases. While specific DNA lesion-bound complexes in crystal structures consist of monomeric AGT, several solution studies have suggested that cooperative DNA binding plays a role in the physiological activities of AGT. Cooperative AGT-DNA complexes have been described by theoretical models, which can be tested by atomic force microscopy (AFM). Direct access to structural features of AGT-DNA complexes at the single molecule level by AFM imaging revealed non-specifically bound, cooperative complexes with limited cluster length. Implications of cooperative binding in AGT-DNA interactions are discussed.

SUBMITTER: Tessmer I

PROVIDER: S-EPMC4111990 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Insight into the cooperative DNA binding of the O⁶-alkylguanine DNA alkyltransferase.

Tessmer Ingrid I Fried Michael G MG

DNA repair 20140216

The O(6)-alkylguanine DNA alkyltransferase (AGT) is a highly conserved protein responsible for direct repair of alkylated guanine and to a lesser degree thymine bases. While specific DNA lesion-bound complexes in crystal structures consist of monomeric AGT, several solution studies have suggested that cooperative DNA binding plays a role in the physiological activities of AGT. Cooperative AGT-DNA complexes have been described by theoretical models, which can be tested by atomic force microscopy ...[more]

PMID: 24553127

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