1ZI0

A Superhelical Spiral in Escherichia coli DNA Gyrase A C-terminal Domain Imparts Unidirectional Supercoiling Bias

Summary for 1ZI0

• Entry DOI: 10.2210/pdb1zi0/pdb
• Descriptor: DNA gyrase subunit A (2 entities in total)
• Functional Keywords: beta pinwheel; gyrase; topoisomerase; spiralling beta pinwheel; dna wrapping, isomerase, dna binding protein
• Biological source: Escherichia coli
• Cellular location: Cytoplasm (Potential): P09097
• Total number of polymer chains: 2
• Total formula weight: 67024.62

Authors

Ruthenburg, A.J.,Graybosch, D.M.,Huetsch, J.C.,Verdine, G.L. (deposition date: 2005-04-26, release date: 2005-05-24, Last modification date: 2024-02-14)

Primary citation

Ruthenburg, A.J.,Graybosch, D.M.,Huetsch, J.C.,Verdine, G.L.
A superhelical spiral in the Escherichia coli DNA gyrase A C-terminal domain imparts unidirectional supercoiling bias
J.Biol.Chem., 280:26177-26184, 2005

PubMed Abstract: DNA gyrase is unique among type II topoisomerases in that its DNA supercoiling activity is unidirectional. The C-terminal domain of the gyrase A subunit (GyrA-CTD) is required for this supercoiling bias. We report here the x-ray structure of the Escherichia coli GyrA-CTD (Protein Data Bank code 1ZI0). The E. coli GyrA-CTD adopts a circular-shaped beta-pinwheel fold first seen in the Borrelia burgdorferi GyrA-CTD. However, whereas the B. burgdorferi GyrA-CTD is flat, the E. coli GyrA-CTD is spiral. DNA relaxation assays reveal that the E. coli GyrA-CTD wraps DNA inducing substantial (+) superhelicity, while the B. burgdorferi GyrA-CTD introduces a more modest (+) superhelicity. The observation of a superhelical spiral in the present structure and that of the Bacillus stearothermophilus ParC-CTD structure suggests unexpected similarities in substrate selectivity between gyrase and Topo IV enzymes. We propose a model wherein the right-handed ((+) solenoidal) wrapping of DNA around the E. coli GyrA-CTD enforces unidirectional (-) DNA supercoiling.

PubMed: 15897198
DOI: 10.1074/jbc.M502838200

Experimental method

X-RAY DIFFRACTION (2.6 Å)