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Are there high-copy number plasmids that utilize a plasmid-addiction system?

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According to the review by Kroll J, Klinter S, Schneider C, Voß I, Steinbüchel A. Plasmid addiction systems: perspectives and applications in biotechnology. Microbial biotechnology. 2010;3(6):634-657. doi:10.1111/j.1751-7915.2010.00170.x., there are high-copy-number Plasmid Addiction Systems (PAS), "specifically the addiction system depending on plasmid‐borne ORT utilizing the lac repressor."

The lac repressor protein (LacI) binds to the lac operator (lacO) and therefore represses the expression of the kanamycin resistance gene. When IPTG is available as an inducer, LacI is titrated by lacO, and the E. coli cells were able to grow in media containing kanamycin due to expression of the corresponding resistance gene. The same result was obtained when high‐copy‐number plasmids harbouring lacO were used for ORT. In this case the plasmid was stably maintained over 72 generations (Williams et al., 1998).

ORT = operator repressor titration

ORT is one of the three main groups of PAS.

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The other answer is a good one, and I just wanted to add a quick note for anyone wondering what a plasmid addiction system is, and to add some more context to the question. This is from my Molecular Genetics of Bacteria Snyder, L. et al. book which is sitting right next to me.

"There is good rationale for plasmid addiction systems, in that they prevent cells cured of the plasmid from accumulating, and thus help ensure survival of the plasmid"[...]"therefor, it was a surprise to discover that similar toxin-antitoxin systems also occur in the chromosome. Some of these are on exchangeable DNA elements, such as genetic islands nd super integrons, and may play a role similar to that of the addiction systems of plasmids."

The example in the book is the P1 phage-encoded Phd-Doc system

enter image description here

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    $\begingroup$ While your answer may be informative, it does not really answer the question which is basically about high copy-number plasmids that utilize plasmid addiction system. $\endgroup$ – WYSIWYG Jan 7 '16 at 8:27

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