4ELY: Ccdbvfi:gyra14ec

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.
PDB ID: 4ELYDownload
MMDB ID: 100156
PDB Deposition Date: 2012/4/11
Updated in MMDB: 2012/05
Experimental Method:
x-ray diffraction
Resolution: 1.93  Å
Source Organism:
Aliivibrio fischeri
Similar Structures:
Biological Unit for 4ELY: tetrameric; determined by author and by software (PISA)
Molecular Components in 4ELY
Label Count Molecule
Proteins (4 molecules)
DNA Gyrase Subunit a(Gene symbol: gyrA)
Molecule annotation
Molecule annotation
Chemicals (3 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB