Linked Life Data

16803589

Source:http://linkedlifedata.com/resource/pubmed/id/16803589

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2006-8-1
pubmed:abstractText
When DNA gyrase is trapped on bacterial chromosomes by quinolone antibacterials, reversible complexes form that contain DNA ends constrained by protein. Two subsequent processes lead to rapid cell death. One requires ongoing protein synthesis; the other does not. The prototype quinolone, nalidixic acid, kills wild-type Escherichia coli only by the first pathway; fluoroquinolones kill by both. Both lethal processes correlated with irreversible chromosome fragmentation, detected by sedimentation and viscosity of DNA from quinolone-treated cells. However, only fluoroquinolones fragmented purified nucleoids when incubated with gyrase purified from wild-type cells. A GyrA amino acid substitution (A67S) expected to perturb a GyrA-GyrA dimer interface allowed nalidixic acid to fragment chromosomes and kill cells in the absence of protein synthesis; moreover, it made a non-inducible lexA mutant hypersusceptible to nalidixic acid, a property restricted to fluoroquinolones with wild-type cells. The GyrA variation also facilitated immunoprecipitation of DNA fragments by GyrA antiserum following nalidixic acid treatment of cells. The ability of changes in both gyrase and quinolone structure to enhance protein synthesis-independent lethality and chromosome fragmentation is explained by drug-mediated destabilization of gyrase-DNA complexes. Instability of type II topoisomerase-DNA complexes may be a general phenomenon that can be exploited to kill cells.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0950-382X
pubmed:author
pubmed:issnType
Print
pubmed:volume
61
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
810-25
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Lethal fragmentation of bacterial chromosomes mediated by DNA gyrase and quinolones.
pubmed:affiliation
Public Health Research Institute, 225 Warren Street, Newark, NJ 07103, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural