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Bluefeather (singleton) lysogeny genes

| posted 02 Feb, 2020 21:34
I'm QCing the singleton Bluefeather (most closely related to clusters FE and FI), and have found some fairly strong evidence for immunity repressor (gp19 - good reverse strand coding potential), and excise (gp20 - forward), but no integrase. There is another HTH at gp21). Plaques do look bullseye, but could be just large halos.

I'll call them HTH DNA binding for now, but would appreciate feedback on whether these should be called as a lysogeny cassette.
| posted 03 Feb, 2020 12:56
Hi Jordan
I'll take a look!
| posted 04 Feb, 2020 18:11
Hi Jordan–
I am always interested in these teeny phages and how they are managing to do all the biology of the big ones.
In this case, I am not able to find an obvious integrase or par system or other mechanism by which lysogeny could be maintained. So I think your plan above is the right way to go— it is possible there is some sort of other unknown equivalent system here, but without bench work, it is hard to say. The integrase could also have been lost during purification– without more phages to compare to, who knows? HTHs all around!
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