CryoEM structures of open dimers of gyrase A in complex with DNA illuminate mechanism of strand passage

Katarzyna M. Soczek, Tim Grant, Peter B. Rosenthal, Alfonso Mondragón*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

5 Scopus citations

Abstract

Gyrase is a unique type IIA topoisomerase that uses ATP hydrolysis to maintain the negatively supercoiled state of bacterial DNA. In order to perform its function, gyrase undergoes a sequence of conformational changes that consist of concerted gate openings, DNA cleavage, and DNA strand passage events. Structures where the transported DNA molecule (T-segment) is trapped by the A subunit have not been observed. Here we present the cryoEM structures of two oligomeric complexes of open gyrase A dimers and DNA. The protein subunits in these complexes were solved to 4 Å and 5.2 Å resolution. One of the complexes traps a linear DNA molecule, a putative T-segment, which interacts with the open gyrase A dimers in two states, representing steps either prior to or after passage through the DNA-gate. The structures locate the T-segment in important intermediate conformations of the catalytic cycle and provide insights into gyrase-DNA interactions and mechanism.

Original languageEnglish (US)
Article numbere41215
JournaleLife
Volume7
DOIs
StatePublished - Nov 1 2018

ASJC Scopus subject areas

  • Neuroscience(all)
  • Immunology and Microbiology(all)
  • Biochemistry, Genetics and Molecular Biology(all)

Fingerprint Dive into the research topics of 'CryoEM structures of open dimers of gyrase A in complex with DNA illuminate mechanism of strand passage'. Together they form a unique fingerprint.

Cite this