Alternative interactions define gyrase specificity in the CcdB family.
Mol Microbiol
; 84(5): 965-78, 2012 Jun.
Article
en En
| MEDLINE
| ID: mdl-22582791
ABSTRACT
Toxin-antitoxin (TA) modules are small operons associated with stress response of bacteria. F-plasmid CcdB(F) was the first TA toxin for which its target, gyrase, was identified. Plasmidic and chromosomal CcdBs belong to distinct families. Conserved residues crucial for gyrase poisoning activity of plasmidic CcdBs are not conserved among these families. Here we show that the chromosomal CcdB(Vfi) from Vibrio fischeri is an active gyrase poison that interacts with its target via an alternative energetic mechanism. Changes in the GyrA14-binding surface of the Vibrio and F-plasmid CcdB family members illustrate neutral drift where alternative interactions can be used to achieve the same functionality. Differences in affinity between V. fischeri and F-plasmid CcdB for gyrase and their corresponding CcdA antitoxin possibly reflect distinct roles for TA modules located on plasmids and chromosomes.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Proteínas Bacterianas
/
Aliivibrio fischeri
/
Inhibidores de Topoisomerasa II
Idioma:
En
Revista:
Mol Microbiol
Asunto de la revista:
BIOLOGIA MOLECULAR
/
MICROBIOLOGIA
Año:
2012
Tipo del documento:
Article
País de afiliación:
Bélgica