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How Many Lysogens?

| posted 28 Sep, 2023 16:24
Hi all- I have been working on generating some lysogens for the Gordonia phage BearBQ. My patch test worked well, and I got good clearing around 8/9 streaks. I have now streaked out the patches to start purification of the bacteria. My question is a practical one- how many of these should I pursue? I streaked out 4 of 8, but do I need to keep all of these going? I guess I am just wondering what the success rate is at this point and how many "backups" I might need to generate a stable lysogen for immunity experiments.

Let me know!

| posted 28 Sep, 2023 17:02
Hi Dane,
In general, we keep one. But until the 'one' has been verified, meaning that the lysogen infection pattern 1) shows homoimmunity to the phage and 2)the phage is detected in the supernatant of the lysogen, more than 1 is advisable. The answer is also dependent on how the different streaks were obtained - from single colonies or out of a 'mesa', because having 4 different clones would be advisable depending on what you want to do. So what questions are you going to investigate with your newly made lysogens?

| posted 28 Sep, 2023 17:08
Hi Debbie!

The patches were from colonies generated from a streak from a mesa that I patch tested. Not totally sure what the plan will be with these- right now I am just exploring! I think some of these lysogeny experiments would be good for our senior research students, so just kind of testing the waters. For now, I will keep working with all four and will test for homoimmunity and phage release in culture.

Thanks for the advice!

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