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Death on Curing (DOC) toxin/antitoxin in Gordonia terrae cluster DL

| posted 11 Jun, 2018 16:20
Goddonia terrae phage DatBoi (cluster DL - available in PECAAN) has a putative toxin/antitoxin pair (reverse genes 131/132 start: 78,758, stop: 78,365 / start: 78,948, stop: 78,751

NCBI and HHPRED show strong evidence that these are a Death on Curing (DOC) toxin/anti-toxin pair where the toxin is a translation elongation inhibitor and the anti-toxin is a transcription factor repressor that down-regulates expression of the stable toxin. These proteins are well described in E.coli phage (phage P1).

There do not seem to be other described components of this system (but I am NOT a toxin expert). However, a third downstream NKF gene has a -4bp overlap and seems to be part of the operon.



Bacterial addiction module toxin Doc inhibits translation elongation through its association with the 30S ribosomal subunit
| posted 11 Jun, 2018 21:45
So at this point, June 2018, we are going to stay with the generic toxin/antitoxin labels for these proteins.
| posted 25 Feb, 2019 19:47
I'll note that there are also nice HHPred matches to a DOC toxin in Gordonia phage Melba, a CV phage - in a reverse gene just before the integrase
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