Next Article in Journal
At the Crossroads of Clinical and Preclinical Research for Muscular Dystrophy—Are We Closer to Effective Treatment for Patients?
Next Article in Special Issue
The Roles of DNA Topoisomerase IIβ in Transcription
Previous Article in Journal
A Rapid Screen for Host-Encoded miRNAs with Inhibitory Effects against Ebola Virus Using a Transcription- and Replication-Competent Virus-Like Particle System
Previous Article in Special Issue
Biochemical Basis of E. coli Topoisomerase I Relaxation Activity Reduction by Nonenzymatic Lysine Acetylation
Article Menu
Issue 5 (May) cover image

Export Article

Open AccessReview
Int. J. Mol. Sci. 2018, 19(5), 1489; https://doi.org/10.3390/ijms19051489

Why Two? On the Role of (A-)Symmetry in Negative Supercoiling of DNA by Gyrase

Institute for Physical Chemistry, University of Muenster, Corrensstrasse 30, 48149 Muenster, Germany
Received: 16 April 2018 / Revised: 9 May 2018 / Accepted: 12 May 2018 / Published: 16 May 2018
(This article belongs to the Special Issue DNA Topoisomerases)
View Full-Text   |   Download PDF [1534 KB, uploaded 16 May 2018]   |  

Abstract

Gyrase is a type IIA topoisomerase that catalyzes negative supercoiling of DNA. The enzyme consists of two GyrA and two GyrB subunits. It is believed to introduce negative supercoils into DNA by converting a positive DNA node into a negative node through strand passage: First, it cleaves both DNA strands of a double-stranded DNA, termed the G-segment, and then it passes a second segment of the same DNA molecule, termed the T-segment, through the gap created. As a two-fold symmetric enzyme, gyrase contains two copies of all elements that are key for the supercoiling reaction: The GyrB subunits provide two active sites for ATP binding and hydrolysis. The GyrA subunits contain two C-terminal domains (CTDs) for DNA binding and wrapping to stabilize the positive DNA node, and two catalytic tyrosines for DNA cleavage. While the presence of two catalytic tyrosines has been ascribed to the necessity of cleaving both strands of the G-segment to enable strand passage, the role of the two ATP hydrolysis events and of the two CTDs has been less clear. This review summarizes recent results on the role of these duplicate elements for individual steps of the supercoiling reaction, and discusses the implications for the mechanism of DNA supercoiling. View Full-Text
Keywords: type II topoisomerase; gyrase; DNA supercoiling; conformational dynamics; single-molecule Förster resonance energy transfer; domain communication type II topoisomerase; gyrase; DNA supercoiling; conformational dynamics; single-molecule Förster resonance energy transfer; domain communication
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Klostermeier, D. Why Two? On the Role of (A-)Symmetry in Negative Supercoiling of DNA by Gyrase. Int. J. Mol. Sci. 2018, 19, 1489.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Int. J. Mol. Sci. EISSN 1422-0067 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top