Publication
Title
Vibrio cholerae ParE2 poisons DNA gyrase via a mechanism distinct from other gyrase inhibitors
Author
Abstract
DNA gyrase is an essential bacterial enzyme required for the maintenance of chromosomal DNA topology. This enzyme is the target of several protein toxins encoded in toxin-antitoxin ( TA) loci as well as of man-made antibiotics such as quinolones. The genome of Vibrio cholerae, the cause of cholera, contains three putative TA loci that exhibit modest similarity to the RK2 plasmid-borne parDE TA locus, which is thought to target gyrase although its mechanism of action is uncharacterized. Here we investigated the V. cholerae parDE2 locus. We found that this locus encodes a functional proteic TA pair that is active in Escherichia coli as well as V. cholerae. ParD2 co-purified with ParE2 and interacted with it directly. Unlike many other antitoxins, ParD2 could prevent but not reverse ParE2 toxicity. ParE2, like the unrelated F-encoded toxin CcdB and quinolones, targeted the GyrA subunit and stalled the DNA-gyrase cleavage complex. However, in contrast to other gyrase poisons, ParE2 toxicity required ATP, and it interfered with gyrase-dependent DNA supercoiling but not DNA relaxation. ParE2 did not bind GyrA fragments bound by CcdB and quinolones, and a set of strains resistant to a variety of known gyrase inhibitors all exhibited sensitivity to ParE2. Together, our findings suggest that ParE2 and presumably its many plasmid-and chromosome-encoded homologues inhibit gyrase in a different manner than previously described agents.
Language
English
Source (journal)
Journal of biological chemistry. - Baltimore, Md
Publication
Baltimore, Md : 2010
ISSN
0021-9258 [print]
1083-351X [online]
Volume/pages
285 :51 (2010) , p. 40397-40408
ISI
000285185500082
Full text (Publisher's DOI)
Full text (publisher's version - intranet only)
UAntwerpen
Publication type
Subject
External links
Web of Science
Record
Identification
Creation 04.10.2018
Last edited 26.09.2021