Molecular Classification
Enzyme, Topoisomerase, DNA Gyrase Subunit
Disease Roles
Infection

DNA Gyrase A Overview

DNA gyrase A is one of the two essential subunits (GyrA and GyrB) that make up DNA gyrase, a specialized type II topoisomerase found in bacteria. This enzyme is unique for its ability to introduce negative supercoils into closed circular double-stranded DNA in an ATP-dependent manner, a function critical for maintaining proper DNA topology during replication and transcription. The functional enzyme is a heterotetramer composed of two GyrA and two GyrB subunits (A₂B₂ complex). GyrA is responsible for binding and encapsulating DNA and contains the active site tyrosine. DNA gyrase maintains appropriate levels of chromosomal supercoiling required for vital processes. It is an attractive target for antibacterial agents.

Mechanism of Action

Inhibition of DNA gyrase activity, stabilization of cleavage complexes

Biological Functions

DNA supercoiling
DNA replication
Transcription
DNA repair
DNA recombination

Disease Associations

Infection

Safety Considerations

  • Antibiotic resistance development

Interacting Drugs

Fluoroquinolones
Aminocoumarins