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Crystallization and preliminary X-ray analysis of the complex of human alpha-thrombin with a modified thrombin-binding aptamer.

ABSTRACT: The thrombin-binding aptamer (TBA) is a consensus DNA 15-mer that binds specifically to human alpha-thrombin at nanomolar concentrations and inhibits its procoagulant functions. Recently, a modified TBA (mTBA) containing a 5'-5' inversion-of-polarity site has been shown to be more stable and to possess a higher thrombin affinity than its unmodified counterpart. The structure of the thrombin-TBA complex has previously been determined at low resolution, but did not provide a detailed picture of the aptamer conformation or of the protein-DNA assembly, while that of the complex with mTBA is unknown. Crystallographic analysis of the thrombin-mTBA complex has been attempted. The crystals diffracted to 2.15 A resolution and belonged to space group I222.

SUBMITTER: Russo Krauss I

PROVIDER: S-EPMC2917304 | biostudies-literature | 2010 Aug

REPOSITORIES: biostudies-literature

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Crystallization and preliminary X-ray analysis of the complex of human alpha-thrombin with a modified thrombin-binding aptamer.

Russo Krauss Irene I Merlino Antonello A Randazzo Antonio A Mazzarella Lelio L Sica Filomena F

Acta crystallographica. Section F, Structural biology and crystallization communications 20100729 Pt 8

The thrombin-binding aptamer (TBA) is a consensus DNA 15-mer that binds specifically to human alpha-thrombin at nanomolar concentrations and inhibits its procoagulant functions. Recently, a modified TBA (mTBA) containing a 5'-5' inversion-of-polarity site has been shown to be more stable and to possess a higher thrombin affinity than its unmodified counterpart. The structure of the thrombin-TBA complex has previously been determined at low resolution, but did not provide a detailed picture of th ...[more]

PMID: 20693681

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