Link to this post | posted 08 Nov, 2025 11:54
pia1@pitt.edu	I see. Thank you!

Link to this post | posted 08 Nov, 2025 02:31
pia1@pitt.edu	Yes, Debbie — everything you said makes sense. One additional thought: since we’re already questioning the purity of the lysate, could it also be possible that the lysogen wasn’t actually established by Arri? I’m thinking I should grow the lysogen in liquid culture and test the phage it releases by picking a plaque and preparing a fresh stock.

Link to this post | posted 07 Nov, 2025 20:19

pia1@pitt.edu

Debbie and Vic, thank you both for all the helpful suggestions! To Vic’s question about reproducibility: No, these experiments haven’t been repeated yet, but they definitely need to be. I first saw the unusual results for Arri over the summer and have been wondering about them ever since. I brought it up today because I’m now seeing similar patterns with other phages on my students’ plates, and I’m worried I might be missing something. To Debbie’s question about lysate purity: I share that concern. I revived Arri by plating the phage stock stored at Pitt and then flooded the webbed plate. So if there was another phage in the original stock at a low titer (low enough not to interfere with sequencing), it could have been propagated along with Arri. Do you have any suggestions for confirming purity, Debbie?

Link to this post | posted 07 Nov, 2025 18:11
pia1@pitt.edu	This time, it did go through. So please ignore what I said about emailing.

Link to this post | posted 07 Nov, 2025 18:10

pia1@pitt.edu

Thanks, Debbie and Vik. I’ve tried several times to attach the results slide as a PPT or JPG, but it isn’t going through. Would it be okay if I email the results instead? I’m trying to share the superinfection immunity test outcomes for phages Dmitri and Arri. Dmitri behaved as expected (no clearing or plaques on the lysogen lawn), but Arri’s results were unexpected (EOP ~10⁻⁴). I’d appreciate any thoughts you might have. Of course, we’ll need to repeat the experiments. 1.74Mb

Link to this post | posted 07 Nov, 2025 15:42
pia1@pitt.edu	Does superinfection immunity completely block a lysogen from being reinfected by the same temperate phage that established the lysogeny?

Link to this post | posted 04 Sep, 2025 00:26
pia1@pitt.edu	debbie fixed! Thanks! Debbie.

Link to this post | posted 03 Sep, 2025 20:35
pia1@pitt.edu	Hi, Could someone please shed some light on why the genome length of phage PestoPenguin is listed as unknown on PhagesDB? The fasta file for this phage is available and when I click on Locally BLAST this genome, the header says ">Gorgonia phage PestoPenguin complete sequence, 60439 bp". Thanks! Ping

Link to this post | posted 06 Aug, 2025 16:18

pia1@pitt.edu

As a molecular biologist for more than 20 years, I'm completely new to TEM work. I'd really appreciate it if someone could share product information for: the "200–400 mesh carbon–formvar-coated copper grids"; the Pelco tab that holds the grid in position shown in this extremely helpful 2-minute video: https://www.youtube.com/watch?v=F0ZNUykXovk&t=41s Thank you in advance for any details, product numbers, vendors, or ordering sources you can share!

Link to this post | posted 25 Jun, 2025 14:46
pia1@pitt.edu	Thanks for the quick response! Debbie. I'll move on to the next step with the homo-immunity test and will keep you posted with more data and most likely, more questions. Ping