Coding

Part:BBa_K3512002

Designed by: Gourav Saha   Group: iGEM20_BITSPilani-Goa_India   (2020-10-20)


CcdA Antitoxin

CcdA antitoxin is part of the CcdA-CcdB toxin-antitoxin system. The target of CcdB is the GyrA subunit of DNA gyrase, an essential type II topoisomerase in Escherichia coli. Gyrase alters DNA topology by effecting a transient double-strand break in the DNA backbone, passing the double helix through the gate and resealing the gaps. The CcdB toxin acts by trapping DNA gyrase in a cleaved complex with the gyrase A subunit covalently closed to the cleaved DNA, causing DNA breakage and cell death in a way closely related to quinolones antibiotics.

In absence of the antitoxin CcdA, the CcdB toxin traps DNA-gyrase cleavable complexes, inducing breaks into DNA and cell death.

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Categories
Parameters
dissociation_constant high affinity site = 3.5748*10^-3 nM
proteinccDA decay rate = 1.152*10^-3 sec-1
proteinsLow affinity site (TAT complex) = 1.36*10^-9 nM